JPH08300928A - Suspension device for vehicle and electric control device for the device - Google Patents

Abstract

(57) [Abstract] [Purpose] Even if the condition of the road surface or the running condition of the vehicle changes, the ride comfort of the vehicle, the damping property of the vehicle body, the grounding property, and the attitude change are always kept good. [Configuration] The vehicle body 2 is provided between the lower arm 21 and the vehicle body 22.
A spring 31 that elastically supports 2 and a damper device 40 that incorporates a damping mechanism that damps the vibration of the vehicle body 22 are provided in parallel. A plurality of coil springs 53 as variable spring elements are inserted between the piston rod 41 protruding from the damper device 40 and the vehicle body 22, and the spring action of the coil spring 53 is selected by the action of the clutch bar 57 and the electromagnetic solenoid 58. To bring out
The total spring constant of the plurality of coil springs 53 can be electrically changed and controlled. Thereby, the damper device 40
By making it possible to electrically change the spring constant of the spring element provided in series, the transmission state of the damping force by the damper device 40 to the vehicle body 22 is variably controlled while the vehicle is traveling.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spring for elastically supporting an unsprung member with respect to an unsprung member between an unsprung member and an unsprung member, and a sprung member for generating a damping force. Of the vehicle suspension device provided in parallel with a damping force generation mechanism for damping the vibration of the unsprung member, and the vehicle suspension device electrically depending on the running road surface state of the vehicle, the running state of the vehicle, and the like. The present invention relates to an electric control device for controlling the same device.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG.
A spring 14 that is provided between a lower arm (unsprung member) 12 and a vehicle body (sprung member) 13 connected to 1 to elastically support the vehicle body 13 with respect to the lower arm 12.
And the spring 1 between the lower arm 12 and the vehicle body 13.
A vehicle suspension device including a damper device 15 that is provided in parallel with the damper 3 and that has a built-in damping force generation mechanism for damping the vibration of the vehicle body 13 caused by the elastic support of the spring 14 is well known. The damper device 15 is connected to the vehicle body 13 via a bush 16 made of an elastic member such as rubber.

As another conventional technique, for example, as disclosed in Japanese Patent Laid-Open No. 5-286326, the damper device 15 is constructed so that its damping coefficient is electrically variably controlled. It is also well known to electrically control the damping coefficient by the damper device 15. In this type of device, the electric control device 17 detects a vibration of the vehicle body 13 caused by, for example, a condition of a traveling road surface, and
The frequency components G1 and G3 corresponding to the resonance frequencies of the sprung member and the unsprung member included in the detected vibration are extracted, and the damping coefficient of the damper device 15 is varied based on the extracted frequency components G1 and G3. The switching control is performed to rapidly attenuate the vibration of the vehicle body 13 related to the resonance frequency or to secure a good ride comfort of the vehicle (see FIGS. 35 and 36).

[0004]

FIG. 35 shows a vehicle suspension device and an electric control device 1 for the same.
7 equivalently, according to which the bush 16
It can be understood that the spring element 16a is connected in series to the damping force generating mechanism 15a built in the damper device 15. However, the spring constant of the spring element 16a is fixed and has the following problems. That is, if the spring constant of the spring element 16a is set to be small, the external force from the road surface is less likely to be input to the vehicle body, so that the riding comfort of the vehicle is improved. However, since the damping force generated by the damping force generation mechanism 15a is less likely to be transmitted to the vehicle body, the vibration of the vehicle body is less likely to be damped, and the grounding property of the vehicle body is also deteriorated, which deteriorates the steerability. In addition, when the vehicle is in a traveling state in which the posture of the vehicle body changes, such as when the vehicle accelerates, decelerates, or turns, pitching and rolling of the vehicle body increase.

On the other hand, if the spring constant of the spring element 16a is set to a large value, the problems of the vehicle body's vibration damping property, ground contact property, and posture change described above are solved, but the vehicle runs on a road surface with many fine irregularities. In this case, even if the damping coefficient of the damping force generating mechanism 15a is set to be small, since the mechanism 15a transmits a part of the input from the road surface to the vehicle body side, the external force from the road surface is directly input to the vehicle body. And the ride comfort of the vehicle deteriorates.

An object of the present invention is to solve the problems such as the ride comfort of the vehicle, the damping property of the vehicle body, the ground contact property, and the posture change, which are related to the fixed spring constant of the spring element 16a. As shown in FIGS. 1 and 2, a spring element 18 whose spring constant can be easily changed while the vehicle is traveling is provided with a damping force between a lower arm (unsprung member) 12 and a vehicle body (sprung member) 13. The principle of solution is to connect the generator 15a in series.

[0007]

SUMMARY OF THE INVENTION Using this principle of solution, the present invention is capable of controlling the riding comfort of a vehicle, the damping property of a vehicle body, the ground contact property, the attitude change, etc. even if the condition of the road surface or the running condition of the vehicle changes. It is a first object of the present invention to provide a vehicle suspension device that can always be kept in good condition. A second object of the present invention is to electrically control the spring constant of the spring element 18 in the vehicle suspension device according to the condition of the traveling road surface, the traveling condition of the vehicle, etc. An object of the present invention is to provide an electric control device for a vehicle suspension that keeps the ride comfort of the vehicle, the damping property of the vehicle body, the ground contact property, and the attitude change. Furthermore, the third aspect of the present invention
The purpose of this is to electrically control the spring constant in an interlocking manner with the damping force generation mechanism 15a, thereby increasing the effect of the damping force generation mechanism 15a. Is also to be provided.

[0008]

In order to achieve the first object, the structural features of the invention according to claims 1 to 3 are the unsprung member (12, 21) and the sprung member. A spring (14, 31) for elastically supporting the sprung member with respect to the unsprung member and a member (13, 22) and a damping force are generated to prevent vibration of the sprung member with respect to the unsprung member. Damping force generation mechanism for damping (15a, 42, 43, 45
a, 45b, 46) in parallel, a spring element (18, 5) arranged in series with the damping force generating mechanism between the unsprung member and the sprung member in a vehicle suspension device.
Liquid in 3, 61, 40a, gas in R3) and spring constant variable mechanism (57, 58, 64, 65a, 65b, 6) that can be electrically controlled to change the spring constant of the spring element.
6, 71-74, 81-83).
Further, this spring element is provided between the damping force generating mechanism and the sprung member, or between the damping force generating mechanism and the unsprung member.

According to this structural feature, by electrically controlling the spring constant varying mechanism while the vehicle is traveling,
Since the spring constant of the spring element connected in series with the damping force generation mechanism can be easily changed, the ride comfort of the vehicle and the damping performance of the vehicle body can be improved even if the condition of the road surface or the running condition of the vehicle changes. It is possible to always maintain good grounding property and posture change. Further, in the vehicle suspension device in which the spring element is provided between the damping force generating mechanism and the sprung member, the influence of the road surface input on the vehicle body can be reduced. In other words, by arranging the spring element on the sprung member side, the mass of the unsprung member that directly receives the road surface input can be reduced, which means that the vibration energy accumulation due to the road surface input is reduced. It becomes easy to suppress the vibration of the vehicle body with respect to.

As shown in FIGS. 3 and 4, the structural feature of the invention according to claim 4 is that it is provided between the unsprung member (21) and the sprung member (22), and the sprung member is a spring. A spring (31) that elastically supports the lower member, and a lower end that is fixed to the unsprung member and that encloses a liquid is divided into upper and lower chambers (R1, R2) by a piston (43). It is composed of a cylinder (40a) and a piston rod (41) whose lower end is connected to a piston and whose upper part is vertically movably protruded from the upper end face of the cylinder. The upper and lower chambers are provided with orifices (42a to 42d, 43a, 43b). )
In a vehicle suspension device including a damper device (40) that generates a damping force with the movement of a piston by communicating with the piston, the suspension device is interposed between an upper end of a piston rod and a sprung member. Multiple springs (5
3) and a spring selection mechanism (57, 5) that is electrically controlled to selectively exert the spring action of a plurality of springs.
8) and are provided.

According to this structure, the plurality of springs are
Between the unsprung member and the sprung member, a damper device that generates a damping force is connected in series. Then, even while the vehicle is running, the spring action of the plurality of springs is selectively exerted by electrically controlling the spring selection mechanism, and the overall spring action of the plurality of springs is adjusted according to the number of springs exerting the spring action. The spring constant is changed.

Further, the structural feature of the invention according to claim 5 is that, as shown in FIG. 5, between the unsprung member (21) and the unsprung member (22), the same spring (31) as described above is provided. In a vehicle suspension device including a damper device (40), an elastic member (61) interposed between the upper end of the piston rod (41) and the sprung member, and having liquid sealed therein. A supply / drainage mechanism (64, 65a, 65b, 66) that is electrically controlled to control the supply / drainage of the liquid in the elastic member and change the amount of the liquid enclosed in the elastic member is provided. With this configuration, the amount of the liquid sealed in the elastic member is changed by electrically controlling the supply / discharge mechanism even while the vehicle is traveling, and the elastic member is compressed according to the sealed amount of the liquid. Because the degree to which it is done changes
The elastic coefficient (spring constant) of the elastic member is changed.

The structure of the invention according to claim 6 is that, as shown in FIG. 6, a spring (31) similar to the above is provided between the unsprung member (21) and the unsprung member (22). And a damper device (40) for a vehicle suspension device, wherein a gas is dissolved in a liquid in a cylinder, and is electrically controlled to control supply and discharge of the gas to the cylinder to be dissolved in the liquid. This is because the supply / discharge mechanism (71 to 74) for changing the amount of the gas to be supplied is provided.
According to this configuration, the amount of the gas dissolved in the liquid in the cylinder is changed by electrically controlling the supply / discharge mechanism even while the vehicle is traveling, and the amount of the gas dissolved in the liquid changes depending on the solubility of the gas. The elastic coefficient (spring constant) is changed.

Further, the constructional feature of the invention according to claim 7 is that, as shown in FIG. 7, a spring (31) similar to the above is provided between the unsprung member (21) and the unsprung member (22). And a damper device (40), which is incorporated in the cylinder (40a) below the piston (43) to form a gas chamber (R3) below the lower chamber (R2). In the vehicle suspension device including the above, there is provided a supply / discharge mechanism that is electrically controlled to control the supply / discharge of gas to / from the gas chamber and change the gas pressure in the gas chamber. According to this configuration, the pressure of the gas in the gas chamber is changed by electrically controlling the supply / discharge mechanism even while the vehicle is traveling, and the elastic coefficient (spring constant) of the gas in the gas chamber is changed according to the pressure. Is changed.

According to the inventions according to claims 4 to 7 which are constructed and operate as described above, like the inventions according to claims 1 to 3, a spring (53) constituting a spring element,
The damper device in which the elastic member (61), the liquid in which the gas in the cylinder (40a) is dissolved, and the gas in the gas chamber (R3) generate a damping force between the unsprung member and the sprung member. Since the spring constants of the spring, the elastic member, the liquid, and the gas which are connected in series with 40 and which constitute the spring element are electrically changed easily even while the vehicle is traveling, the state of the traveling road surface and the traveling state of the vehicle. Even if the above changes, the ride comfort of the vehicle, the damping property of the vehicle body, the ground contacting property, and the posture change can be always kept good. Further, since the spring, the elastic member and the liquid which constitute the spring element of the invention according to claims 4 to 6 are inserted between the damper device and the sprung member, the influence of the road surface input on the vehicle body is reduced. it can. Furthermore, since the liquid and the gas that compose the spring element of the invention according to claims 6 and 7 are enclosed in the cylinder, the entire apparatus can be made compact.

In order to achieve the second object, the structural feature of the invention according to claim 8 is that the same spring, damping force generating mechanism, spring element and spring constant as those of the invention according to claim 1 are used. A detection means (101, 104, 10) for detecting a state in which a damping force generation mechanism generates a damping force, in an electric control device for a vehicle suspension device including a mechanism.
5,204,208,216 or 121,122,12
4, 125, 606, 634, 648) and spring constant control means (206, 210, 214, 218) for controlling the spring constant variable mechanism to increase the spring constant of the spring element when the state is detected by the detection means. , 220, 224 or 610, 638, 652, 662, 224).

According to the invention of claim 8 configured as described above, when the sprung member fluctuates in the vertical direction with respect to the unsprung member, and the damping force generating mechanism is in a state of generating a damping force, The detection means detects the same state, and at the time of the detection, the spring constant of the spring element is controlled to increase by the action of the spring constant control means. As a result, the damping force generated by the damping force generating mechanism can be efficiently transmitted to the sprung member, and the vibration of the sprung member is favorably suppressed without impairing the function of the mechanism. On the other hand, when the detecting means does not detect the generation state of the damping force, the spring constant of the spring element is kept small, so that small vibration of the sprung member and road surface input are absorbed by the spring element, and the ride comfort of the vehicle is good. Kept in.

[0018] According to a ninth aspect of the present invention, there is provided an electric control device for a vehicle suspension device including a spring, a damping force generating mechanism, a spring element, and a spring constant varying mechanism. Vibration detecting means (101, 104, 105, 204, 208, for detecting the vibration of the member,
216) and spring constant control means (206, 210, 214, 218, 2) for controlling the spring constant variable mechanism to increase the spring constant of the spring element when the detected vibration is large.
20, 224).

Further, the vibration detecting means of the invention according to claim 10 is for detecting the vibration of the sprung member in a specific frequency range.

According to the inventions according to claims 9 and 10 configured as described above, in the state where the sprung member vibrates and the damping force generating mechanism generates the damping force, the vibration detecting means and the spring constant controlling means are operated. Due to the action, the spring constant of the spring element is controlled to increase. Therefore, similarly to the invention according to claim 8, the function of the damping force generating mechanism is not impaired, and the vibration of the sprung member is well suppressed. Further, when the vibration of the sprung member is small, the spring constant of the spring element is kept small and the ride comfort of the vehicle is kept good.
Particularly, according to the invention of claim 10, the vibration detecting means can detect the vibration of the sprung member in the specific frequency region, for example, the vibration of the sprung member corresponding to the resonance frequency of the sprung member or the unsprung member, "Shaking vibration" and "vibration due to unsprung resonance" of sprung members that tend to develop into large vibrations can be damped well, and for other vibrations that give a "crackiness" to the occupant. The vibration of the sprung member and the road surface input are absorbed by the spring element, so that the ride comfort of the vehicle can be kept good.

According to an eleventh aspect of the present invention, there is provided an electric control device for a vehicle suspension device including the spring, a damping force generating mechanism, a spring element, and a spring constant varying mechanism. Detecting means (12) for detecting a driving operation of a vehicle that causes a change in posture of a member (vehicle body)
1,122,124,125,606,634,64
8) and a spring constant control means (610, 638, 65) for increasing the spring constant of the spring element by controlling the spring constant variable mechanism in response to the driving operation of the vehicle detected by the detection means.
2, 662, 224).

According to the eleventh aspect of the invention configured as described above, the posture of the sprung member is changed (roll, dive, squat) by the turning operation of the steering wheel, the depression operation of the accelerator pedal or the brake pedal, and the like. In this case, the detecting means detects the driving operation of these vehicles, and the spring constant controlling means controls the spring constant varying mechanism to increase the spring constant of the spring element. Therefore, when the damping force generation mechanism generates a damping force with respect to the posture change of the sprung member due to the driving operation, the spring constant of the spring element is set to a large value. Can be efficiently transmitted to the sprung member, the function of the mechanism is not impaired, and the vibration of the sprung member due to a change in posture is favorably suppressed. On the other hand, when the detecting means does not detect the driving operation, the spring constant of the spring element is kept small, so that a small vertical movement of the sprung member (particularly the initial vertical movement) and the road surface input are absorbed by the spring element, and The ride comfort of the car is kept good.

[0023] According to a twelfth aspect of the present invention, there is provided an electrical control device for a vehicle suspension device comprising the spring, a damping force generating mechanism, a spring element, and a spring constant varying mechanism, and a vehicle speed control device. The vehicle speed detection means (123) for detecting and the spring constant control means (620, 624, 224) for controlling the spring constant variable mechanism to increase the spring constant of the spring element when the detected vehicle speed is high. It is in.

In the invention according to claim 12 configured as described above, when the vehicle is traveling at a high speed, the spring constant of the spring element is set to a large value by the vehicle speed detection means and the spring constant control means. Therefore, when the vehicle running at high speed turns by turning the steering wheel, the damping force generated by the damping force generation mechanism due to the posture change (roll) of the sprung member is efficiently transmitted to the sprung member. As a result, the function of the mechanism is not impaired, and the vibration of the sprung member due to the change in posture is properly suppressed. On the other hand, when the vehicle speed is low, the spring constant of the spring element is kept small, so a small attitude change (especially the initial attitude change) of the sprung member and the road surface input are absorbed by the spring element, and the ride comfort of the vehicle is good. Kept in.

The structural feature of the invention according to claim 13 is applied to a vehicle suspension device provided with the spring, a damping force generating mechanism, a spring element and a spring constant varying mechanism, and is controlled by the spring constant varying mechanism. A signal is output to set the spring constant of the spring element to a target spring constant represented by the control signal in an electrical control unit for a suspension system for a vehicle, between the resonance frequencies of the sprung member and the unsprung member. Detecting means (101, 116, 117, 604) for detecting the distributed vibration component of the sprung member, and a spring constant for restricting the target spring constant represented by the control signal to a small value when the detected vibration component is large. Regulatory means (612
~ 618, 626-632, 640-646, 654-
And 660).

According to the thirteenth aspect of the invention configured as described above, the sprung member distributed between resonance frequencies of the sprung member and the unsprung member by the action of the detecting means and the spring constant regulating means. When the vibration component is large, the spring constant of the spring element is limited to a small value. This vibration component is a component that gives the occupant a rugged feeling, and since this vibration is absorbed by the spring element, the ride comfort of the vehicle is kept good.

The structural feature of the invention according to claim 14 is applied to a vehicle suspension device provided with the spring, a damping force generating mechanism, a spring element and a spring constant varying mechanism, and the spring constant varying mechanism includes a spring. Relative speed detection means (102, 1) for detecting the relative speed of the sprung member with respect to the unsprung member in an electric control device for a vehicle suspension device that outputs a control signal for constant switching control.
06) and a permitting means (304) for permitting the output of the control signal when the relative speed detected by the relative speed detecting means becomes substantially “0”.

In the invention according to claim 14 configured as described above, as in the invention according to claim 1, the spring constant of the spring element connected in series with the damping force generating mechanism during traveling of the vehicle is electrically changed. Since it can be controlled to switch to
Even if the state of the road surface or the running state of the vehicle changes, the riding comfort of the vehicle, the damping property of the vehicle body, the grounding property, and the posture change can be always kept good. In the switching control of the spring constant, the spring constant of the spring element is changed only when the relative speed of the sprung member to the unsprung member is substantially "0" due to the action of the relative speed detecting means and the permitting means. Therefore, when the spring element is expanding and contracting, the spring constant of the spring element does not change, so that the occupant is not shocked by the change of the spring constant, and the ride comfort of the vehicle is improved. To be kept.

The structural feature of the invention according to claim 15 is applied to a vehicle suspension device provided with the spring, a damping force generating mechanism, a spring element and a spring constant varying mechanism, and the spring constant varying mechanism is electrically operated. An electric control device for a vehicle suspension device that dynamically controls the spring constant of a spring element to change the spring constant gradually when switching the spring constant in the electric control device. A switching control means (416) for forming a control signal and outputting it to the spring constant varying mechanism is provided.

Also in the invention according to claim 15 configured as described above, as in the invention according to claim 14, the spring constant can be electrically switched and controlled, the condition of the traveling road surface and the traveling of the vehicle. Even if the state or the like changes, the ride comfort of the vehicle, the vibration damping property of the vehicle body, the ground contact property, the posture change, and the like can always be kept good. Further, in the switching control of the spring constant, even if the spring constant of the spring element is largely changed, the spring constant is gradually changed by the action of the switching control means, so that the occupant is shocked by the change of the spring constant. It will not be received and the ride comfort of the vehicle will be maintained.

In order to achieve the third object, the structural feature of the invention according to claim 16 is that the same spring, damping force generating mechanism, spring element and variable spring constant as those of the invention according to claim 1 are provided. In addition to the vehicle suspension device equipped with the mechanism, a damping coefficient variable mechanism (48, 49) capable of electrically controlling the damping coefficient of the damping force generating mechanism and a damping coefficient variable mechanism and a spring constant variable mechanism are provided. The electric control device (17, 67, 75, 84, 100) for electrically controlling is provided.

According to the sixteenth aspect of the invention configured as described above, the damping coefficient varying mechanism changes the damping coefficient of the damping force generating mechanism, and the spring constant varying mechanism changes the spring constant of the spring element. In addition, the electric control device electrically controls the both variable mechanisms. Therefore, for example, when a damping force is required, the spring constant of the spring element is increased so that the damping force by the damping force generation mechanism is efficiently transmitted to the sprung member. The vibration of the sprung member can be quickly damped by increasing the damping coefficient. Further, when the damping force is unnecessary, both the damping coefficient of the damping force generating mechanism and the spring constant of the spring element are controlled to be small, so that the ride comfort of the vehicle can be kept good. in this way,
According to the present invention, it is possible to easily achieve both the damping of the vibration of the sprung member and the riding comfort required for the vehicle suspension device.

A structural feature of the seventeenth aspect of the present invention is that an electric control for a vehicle suspension device comprising the spring, a damping force generating mechanism, a spring element, a damping coefficient varying mechanism and a spring constant varying mechanism. First vibration detecting means (101, 103) for detecting the vibration of the sprung member
A second vibration detecting means (101, 104, 105) for detecting the vibration of the sprung member in a specific frequency region, and a damping coefficient variable mechanism when the vibration of the sprung member detected by the first vibration detecting means is large. Then, the first control means (228, 228, which sets a large damping coefficient of the damping force generating mechanism).
230, 234) and second control means (204) for setting the spring constant of the spring element to a large value by controlling the spring constant variable mechanism when the vibration of the sprung member in the specific frequency region detected by the second vibration detecting means is large. ~ 220,224). In this case, the specific frequency region is
For example, the invention according to claim 18 corresponds to at least one of the resonance frequencies of the sprung member and the unsprung member.

According to the seventeenth and eighteenth aspects of the present invention configured as described above, due to the actions of the second vibration detecting means and the second control means, the vibration of the sprung member tends to increase in a specific frequency region (for example, In the resonance frequency region of the sprung member and the unsprung member), the spring constant of the spring element is set to be large. Therefore, in this specific frequency range, the damping force generated by the damping force generation mechanism is efficiently transmitted to the sprung member, and the damping control of the vibration of the sprung member is efficiently performed by the actions of the first vibration detection means and the first control means. Often done, the large vibrations of the sprung member can be quickly dampened. In addition, since the spring constant of the spring element is set to be small outside the specific frequency range, the vibration of the sprung member and the road surface input are absorbed by the spring element, and the ride comfort of the vehicle is kept good.

The structure of the invention according to claim 19 is the electric control for a vehicle suspension device comprising the spring, a damping force generating mechanism, a spring element, a damping coefficient varying mechanism and a spring constant varying mechanism. The apparatus includes a sensor (101) for detecting vibration of a sprung member, and a damping coefficient varying mechanism for detecting a vibration by a sensor when a vibration component belonging to a low frequency region is large among vibrations of the sprung member detected by the sensor. The damping coefficient of the damping force generation mechanism is set larger as the vibration of the sprung member is increased.
When the vibration component is small, the first control means (104, 228 to 234, 504) that controls the damping coefficient variable mechanism to set the damping coefficient of the damping force generation mechanism to be small, and the vibration of the sprung member detected by the sensor. When the vibration of the sprung member belonging to the specific frequency region is large, the spring constant variable mechanism is controlled to set the spring constant of the spring element to a large value, and in other cases, the spring constant variable mechanism is controlled to control the spring element. Second control means (104, 1) for setting a small spring constant
05, 204-224). In this case, the specific frequency corresponds to at least one of the resonance frequencies of the sprung member and the unsprung member, as in the invention according to claim 20, for example.

According to the inventions according to claims 19 and 20 configured as described above, as in the inventions according to claims 17 and 18, the resonance frequency of the sprung member and the unsprung member is within a specific frequency range. (Region), the damping control of the vibration of the sprung member by the action of the sensor and the first control means can be efficiently performed, and the vibration of the sprung member can be quickly damped. In this case, the first control means sets the damping coefficient of the damping force generation mechanism to be small when the vibration component belonging to the high frequency region of the vibration of the sprung member is large. As a result, due to the poor response of the damping force generation mechanism,
In the high frequency range where the mechanism cannot properly damp the vibration of the sprung member, the ride comfort of the vehicle is preferentially performed without wastefully performing the vibration damping control.

Further, a structural feature of the invention according to claim 21 is that an electric control for a vehicle suspension device comprising the spring, a damping force generating mechanism, a spring element, a damping coefficient varying mechanism and a spring constant varying mechanism. The device is provided with sensor means (101, 102, 10) for detecting the vibration of the sprung member.
6) and when the vibration component corresponding to the resonance frequency of the sprung member is large among the vibrations of the sprung member detected by the sensor means, the damping coefficient variable mechanism is controlled to change the vibration of the sprung member detected by the sensor means. The damping coefficient of the damping force generation mechanism is set to a first value that increases as the value increases, and when the vibration component corresponding to the resonance frequency of the unsprung member in the detected vibration of the sprung member is large, the damping coefficient is variable. The mechanism is controlled to set the damping coefficient to a small second value, and when the vibration components corresponding to the respective resonance frequencies of the unsprung member and the sprung member out of the detected vibrations of the sprung member are not large, damping is performed. First control means (226 to 234, 504 to 512) for controlling the coefficient variable mechanism to set the damping coefficient to a third value smaller than the second value.
When the vibration of the sprung member corresponding to each resonance frequency of the sprung member and the unsprung member is large among the vibrations of the sprung member detected by the sensor means, the spring constant variable mechanism is controlled to control the spring element. The second control means (204 to 224) sets a large spring constant.

According to the twenty-first aspect of the invention configured as described above, when the vibration component of the sprung member corresponding to the resonance frequency of the sprung member is large, the damping coefficient of the damping force generating mechanism is equal to that of the sprung member. It is set to a first value that increases as the vibration increases. When the vibration component of the sprung member corresponding to the resonance frequency of the unsprung member is large, the damping coefficient is set to a small second value. In other cases, the damping coefficient is set to the third value which is smaller than the second value. This allows
The vibration of the sprung member is more finely controlled than the invention described in claims 19 and 20, and the vibration of the sprung member corresponding to the resonance frequency of the unsprung member is well suppressed. It is possible to better achieve both the damping and the improvement of the riding comfort of the vehicle.

[0039]

Embodiments of the present invention will be described below. First, various mechanical structural examples of the suspension device according to the present invention will be described, and then various examples of an electric control device for the suspension device applied to the device will be described.

A. First Embodiment of Suspension Device As shown in FIG. 3, the suspension device according to the first embodiment has a lower arm (unsprung member) 21 and a vehicle body (sprung member) connected to wheels (not shown) at outer ends. The spring 31 and the damper device 40 are arranged in parallel with each other. The spring 31 elastically supports the vehicle body 22 with respect to the lower arm 21, and is held at its lower end by a retainer 32 fixed on the outer peripheral surface of the cylinder 40a of the damper device 40, and at its upper end, the vehicle body 22.
It is held via a bush 34 on the lower surface of the outer end portion of the fixing plate 33 fixed to the lower surface of the circular opening.

The damper device 40 has a built-in damping force generating mechanism to damp the vibration of the vehicle body 22 with respect to the lower arm 21. As shown in FIGS.
It is tiltably connected to the lower arm 21 at the lower end of a. From the upper surface of the cylinder 40a, the piston rod 41
Is protruded, and a stepped sleeve 42 formed in a cylindrical shape is provided at the lower end of the rod 41.

A piston 43 for liquid-tightly partitioning the interior of the cylinder 40a into upper and lower oil chambers R1 and R2 is fixed on the outer periphery of the lower portion of the sleeve 42, and hydraulic oil (liquid) is stored in the upper and lower oil chambers R1 and R2. It is enclosed. The upper and lower oil chambers R1 and R2 communicate with each other via oil passages 43a and 43b provided in the piston 43, and oil passages 42a to 4a provided in the sleeve 42.
It is designed to communicate via 2d. The oil passages 42a to 42d, 43a, 43b form orifices. A free piston 4 is provided below the lower oil chamber R2.
4 defines a gas chamber R3, and the gas chamber R3 is divided into upper and lower oil chambers R1 by the amount of invasion of the piston rod 41 into the upper oil chamber R1 by the vertical movement of the free piston 44.
Absorbs volume changes of 1 and R2.

A leaf valve 45a that opens only downward is attached to the lower open end of the oil passage 43a. The valve 45a extends from the upper oil chamber R1 to the lower oil chamber R2 only when the piston 43 moves upward. Allow movement of hydraulic oil. A leaf valve 4 that opens only upward at the upper open end of the oil passage 43b.
5b is assembled, and the valve 45b is provided from the lower oil chamber R2 to the upper oil chamber R only when the piston 43 moves downward.
Allow hydraulic oil to move to 1.

On the inner circumference of the oil passage 42b of the sleeve 42, a cylindrical orifice member 46 having a tapered portion 46a on its outer peripheral surface is housed so as to be movable in the vertical direction. Vertical movement causes taper portion 46a
The amount of restriction of the orifice formed between the sleeve and the peripheral wall of the oil passage 42b of the sleeve 42 can be continuously changed. In this damper device 40, as the piston 43 moves up and down, a damping force is generated by the passage resistance to the hydraulic oil passing through the leaf valves 45a and 45b and the orifice, and the orifice is throttled. The damping coefficient is changed by changing the amount.

This orifice member 46 is a drive rod 47.
Is fixed to the lower portion of the rod 47, and the upper end portion of the rod 47 is screwed to the nut 48 via a large number of balls. Nut 4
8 is a step motor 49 which constitutes an electric actuator.
Is driven to rotate, and the rotation causes the drive rod 47 and the orifice member 46 to move up and down. The step motor 49 is a rotor 49a having a nut 48 fixed on the inner peripheral surface.
And a plurality of permanent magnets 49b fixed on the outer circumference of the rotor 49a along the circumferential direction at predetermined intervals, and a plurality of coils 49c facing the magnet 49b and annularly arranged at predetermined intervals. Note that, as shown in FIG. 4, the cylinder 40a actually has a double structure.

In this damper device 40, the drive rod 47 moves up and down as the rotor 49a rotates by electrically controlling the step motor 49 from the outside. The vertical movement of the drive rod 47 causes the orifice member 46 to switch the throttle amount between the oil passages 42b to 42d, so that the damper device 40 switches its damping coefficient in multiple stages. Therefore, the damping force generating mechanism according to the present invention includes the sleeve 42, the piston 43, and the leaf valve 4.
5a, 45b and the orifice member 46,
The damping coefficient variable mechanism in the present invention is composed of a nut 48 and a step motor 49.

A movable plate 51 is fixed to the upper end of the piston rod 41 in parallel with the fixed plate 33. Guide rods 52 are erected at appropriate positions on the upper surface of the movable plate 51, and these guide rods 52 are slidable on the inner peripheral surface of a through hole 33 a provided in the fixed plate 33 to be movable. The plate 51 is moved up and down while keeping parallel to the fixed plate 33. Further, on the upper surface of the movable plate 51, n (for example, several to several tens) coil springs 53 having the same spring constant k are vertically fixed at their respective lower ends. The upper end of each coil spring 53 is fixed to a stopper plate 54a provided at the lower end of the control rod 54.
The reference numeral 4 slidably penetrates the inner peripheral surface of a through hole 33b provided in the fixed plate 33.

Each control rod 54 also penetrates a casing 55 fixed to the upper surface of the fixed plate 33 so as to be vertically movable. The casing 55 is the fixed plate 33.
An L-shaped frame 56 fixed to the upper surface of the is housed. A through hole 56a is formed in the horizontal portion of the frame 56, and the upper end portion of the control rod 54 is slidably passed through the hole 56a. Also, the casing 5
5 also includes a clutch bar 57 for pulling the control rod 54 laterally and an electromagnetic solenoid 58 for driving the bar 57 laterally.

The clutch bar 57 is supported by a support frame 59 fixed to the upper surface of the fixed plate 33 so as to be displaceable in the axial direction, and its tip end is bent in a hook shape so as to engage with the middle part of the control rod 54. Has become.
The clutch bar 57 is constantly urged to the right in the figure by springs 57a having both ends connected to the casing 55 and the clutch bar 57, respectively. Electromagnetic solenoid 5
8 is also fixed to the casing 55 and sucks the clutch bar 57 to the left in the figure in the energized state.

In the vehicle suspension device constructed as described above, when the electromagnetic solenoid 58 is de-energized, the clutch bar 57 is displaced to the right in FIG. 3 by the biasing force of the spring 57a. In this state, the engagement between the tip of the clutch bar 57 and the control rod 54 is released, and the stopper plate 54a is fixed to the fixed plate 3.
Until the rod 3 comes into contact with the fixed plate 33,
Also, it can move up and down freely without being restrained by the frame 56. Therefore, until the stopper plate 54a contacts the fixed plate 33, the coil spring 53 corresponding to the electromagnetic solenoid 58 that is not energized does not exert a spring action (the spring constant of the coil spring 53 is kept at "0"). .

On the other hand, when the electromagnetic solenoid 58 is energized,
The clutch bar 57 is displaced to the left in FIG.
The tip of the pulls the control rod 54 in the same direction. In this state, the control rod 54 is engaged with the inner peripheral surface of each of the through holes 33b and 56a of the clutch bar 57, the fixed plate 33, and the frame 56, and the rod 54 is equivalent to that fixed to the fixed plate 33. Become. Therefore, the coil spring 53 corresponding to the energized electromagnetic solenoid 58 exhibits a spring action, and its spring constant becomes a predetermined value k of the spring 53.

As described above, n coil springs 53 are provided, and each coil spring 53 can be selectively operated by energizing or de-energizing the electromagnetic solenoid 58 corresponding to each coil spring 53. m
When (m <n) electromagnetic solenoids 58 are energized, m
The individual coil springs 53 function, which is equivalent to inserting a spring element having a spring constant mk between the movable plate 51 (damper device 40) and the vehicle body 22. Therefore, according to the suspension device of the first embodiment, the spring constant of the spring element composed of the n coil springs 53 provided between the damper device 40 and the vehicle body 22 is set to 0, k, 2k, ...,
You can select and set any of nk.

Although the spring constants of the n coil springs 53 are all set to the same value in the above example,
By varying the spring constant of each coil spring 53 variously, the variation width and variation range of the spring constant of the spring element composed of the n coil springs 53 can be variously changed.

As described above, in the suspension device according to the first embodiment, the lower arm (unsprung member) is used.
A spring element composed of a plurality of coil springs 53 is provided in series with the damping force generating mechanism in the damper device 40 between the vehicle body 21 and the vehicle body (spring member) 22, and the clutch bar 57, the electromagnetic solenoid 58, etc. Therefore, a spring constant variable mechanism (spring selection mechanism) for selectively variably exerting the spring action of each coil spring 53 to electrically variably control the spring constant of the spring element is provided.
Therefore, according to the suspension device, the spring constant of the spring element connected in series with the damper device 40 can be easily changed while the vehicle is running, so that the running road surface state, the running state of the vehicle, and the like change. However, the ride comfort of the vehicle, the damping property of the vehicle body, the ground contact property, and the attitude change can be always kept good.

Further, in the suspension device according to the embodiment, since the spring element is provided between the damping force generating mechanism in the damper device 40 and the vehicle body 22, the influence of the road surface input on the vehicle body is reduced. it can. In other words,
By arranging the spring element on the side of the sprung member, the mass of the unsprung member that directly receives the road surface input can be reduced, which means that the vibration energy accumulated by the road surface input is reduced. Vibration can be easily suppressed. In this embodiment, the coil spring 5
Although 3 is used as a spring element, a plate-shaped spring or another shape of spring may be used as the spring element. Also,
The spring element may be made of an elastic member such as rubber including various springs.

B. Second Embodiment of Suspension Device A suspension device according to a second embodiment of the present invention is shown in FIG.
As shown in FIG. 5, the spring 31 and the damper device 40, which are constructed and assembled in the same manner as the first embodiment, are provided. The characteristic of the second embodiment is that the damper device 40 and the vehicle body 2 are
The elastic member 61 that constitutes a spring element is interposed between the fixing plate 33 fixed to the No. 2 and the fixing plate 33.

The elastic member 61 is formed of a material such as rubber into an annular shape and is made of a deformable resinous skin 61.
An annular cavity 61b, which is covered with a and is filled with hydraulic oil (liquid), is formed. The elastic member 61 thus configured is fixed to the upper surface of the movable plate 62 fixed to the intermediate portion of the piston rod 41 at the lower surface, and is fixed to the lower surface of the fixed plate 33 at the upper surface. The piston rod 41 extends above the movable plate 62, penetrates through the through hole 61c of the elastic member 61 so as to be able to advance and retract, and slidably penetrates through the through hole 33c provided in the fixed plate 33, so that the damper device 40. It acts as a guide for the vertical movement of.

The elastic member 61 is provided with an inflow / outflow port 61d communicating with the cavity 61b.
1d is both oil chambers R4, R of the cylinder 64 via the conduit 63.
It communicates with 5. A piston 65 is placed in the cylinder 64.
A and 65b are liquid-tightly and slidably incorporated, and a piezoelectric actuator 66 as an electric actuator having piezoelectric elements stacked is interposed between the pistons 65a and 65b. The piezoelectric actuator 66 is an electric control device 67.
The thickness of the piston 65 is changed in response to the voltage signal from the piston 65.
a and 65b are displaced up and down in the figure. The cylinder 6
4 and the electric control device 67 are assembled at appropriate places on the vehicle body 22.

In the vehicle suspension device according to the second embodiment having the above-described structure, the electric control device 67 is used.
When the control voltage is applied to the piezoelectric actuator 66, the thickness of the actuator 66 increases in proportion to the applied voltage. Therefore, the pistons 65a and 65b are displaced up and down in proportion to the applied voltage to supply the working oil in the upper and lower oil chambers R4 and R5 to the cavity 61b of the elastic member 61. Since the supplied hydraulic oil presses the thick portion of the elastic member 61, the density of the elastic member forming the same portion increases, and the spring constant of the elastic member 61 is proportional to the magnitude of the applied voltage. Change. In addition, the stepper motor 49 of the damper device 40
The rotational position of is also controlled by the electric control device 67, and the damping coefficient in the damper device 40 is also switched.

As described above, in the suspension device according to the second embodiment, the lower arm (unsprung member) is used.
21 and the vehicle body (sprung member) 22 between the elastic member 61.
The spring element configured as described above is provided in series with the damping force generating mechanism including the sleeve 42, the piston 43, the leaf valves 45a and 45b, and the orifice member 46 in the damper device 40. Then, the cylinder 64 and the piston 65
a, 65b, a piezoelectric actuator 66, etc., and controls the supply and discharge of hydraulic oil to and from the elastic member 61.
A spring constant variable mechanism (supply / discharge mechanism) for electrically variably controlling the spring constant (elasticity) of is provided. Therefore, even with this suspension device, the spring constant of the spring element connected in series with the damper device 40 can be easily changed while the vehicle is traveling, and the spring element can be replaced by the damper device 4.
Since it is provided between 0 and the vehicle body 22, the same effect as that of the first embodiment can be obtained.

C. Third Embodiment of Suspension Device A suspension device according to a third embodiment of the present invention is shown in FIG.
As shown in FIG. 5, the spring 31 and the damper device 40, which are constructed and assembled in the same manner as the first and second embodiments, are provided. The feature of the third embodiment resides in that the working oil (liquid) enclosed in the cylinder 40a in the damper device 40 has a spring action. In this case, the upper end of the piston rod 41 is fixed to the fixed plate 33 fixed to the vehicle body 22.

The inflow / outflow port 4 is provided above the cylinder 40a.
0a1 is provided, and air (gas) is introduced into the cylinder 40a through the port 40a1. The air introduced into the cylinder 40a dissolves in the hydraulic fluid (very fine air particles are mixed in the hydraulic fluid).
Then, in this example, the volume of the hydraulic oil in the cylinder 40a hardly changes, and the elastic coefficient (spring coefficient) of the hydraulic oil is the same.
Is utilized as the solubility of air in hydraulic oil (the amount of air in the cylinder 40a) decreases as it increases. Therefore, the spring element of the present invention corresponds to the hydraulic oil that is enclosed in the cylinder 40a and dissolves air (gas).

The inflow / outflow port 40a1 is connected to the air pumps 73, 7 via a filter 71 and a three-position switching valve 72.
4 is connected. The filter 71 uses the difference in particle size to prohibit passage of the hydraulic oil in the upper oil chamber R1, and allows only passage of air (gas). The three-position switching valve 72 is provided with an electromagnetic solenoid 72a, and the three-position switching valve 72 is switched and controlled by the energization control of the electromagnetic solenoid 72a by the electric control device 75. The air pumps 73 and 74 are also driven and controlled by the electric control device 75. A pressure sensor 76 is provided between the three-position switching valve 72 and the filter 71 in order to control the amount of air dissolved in the hydraulic oil in the cylinder 40a. 7
5 are supplied. Note that the filter 7
1, 3 position switching valve 72, air pumps 73, 7
4, the electric control device 75 and the pressure sensor 76 are assembled at appropriate places on the vehicle body 22.

In the vehicle suspension device according to the third embodiment having the above-mentioned structure, the electric control device 75 is used.
Controls the electromagnetic solenoid 72a to set the three-position switching valve 72 to the lower position shown in the figure and to operate the air pump 74.
2 and the filter 71, and is guided into the cylinder 40a. Therefore, in this case, the solubility of air in the hydraulic oil in the cylinder 40a increases, and the elastic coefficient (spring constant) of the hydraulic oil decreases. The electric control device 75 controls the electromagnetic solenoid 72a of the three-position switching valve 72 by determining when the elastic coefficient of the hydraulic oil reaches a desired value from the pressure value detected by the pressure sensor 76. While switching 72 to the central position shown in the figure,
The operation of the air pump 74 is stopped. As a result, the inflow of air to the cylinder 40a is stopped, so that the elastic coefficient of operation in the cylinder 40a is maintained at the desired value.

On the other hand, if the electric control unit 75 controls the electromagnetic solenoid 72a to set the three-position switching valve 72 to the position shown in the figure and the air pump 73 is operated, only the air (gas) in the cylinder 40a is discharged. It is discharged to the outside through the filter 71 and the 3-position switching valve 72. Therefore, in this case, the solubility of air in the hydraulic oil in the cylinder 40a decreases, and the elastic coefficient (spring constant) of the hydraulic oil increases. In this case as well, the electric control device 75 cooperates with the pressure sensor 76 to switch the three-position switching valve 72 to the central position in the drawing and the air pump 73 when the elastic coefficient of the hydraulic oil reaches a desired value. Stop the operation of. As a result, the cylinder 40
Since the outflow of air to a is stopped, the cylinder 40
The elastic modulus of the hydraulic oil in a is maintained at the desired value. Further, the rotational position of the step motor 49 of the damper device 40 is also controlled by the electric control device 75, and the damping coefficient of the damper device 40 is also switched.

As described above, in the suspension device according to the third embodiment, the lower arm (unsprung member) is used.
21 and the vehicle body (spring member) 22 between the cylinder 40
A spring element made of hydraulic oil (liquid) that is enclosed in a and dissolves air (gas) is used to generate a damping force that is made up of a sleeve 42, a piston 43, leaf valves 45a and 45b, and an orifice member 46 in the damper device 40. It was provided in series with the mechanism. The filter 71, the three-position switching valve 72, the air pumps 73, 74, etc. are used to control the supply and discharge of air (gas) to and from the cylinder 40a to electrically change the elastic coefficient (spring constant) of the working oil (liquid). A spring constant variable mechanism (supply / discharge mechanism) for variably controlling is provided. Therefore, even with this suspension device, the spring constant of the spring element connected in series with the damper device 40 can be easily changed while the vehicle is traveling, and a part of the hydraulic oil that constitutes the spring element is the damping force generating mechanism. And car body 2
Since it is located between the first and second
The same effect as that of the embodiment can be enjoyed. Further, in the first embodiment, the working oil (liquid) enclosed in the cylinder 40a, which is the spring element, is configured as a part of the damper device 40, so that the entire device is compact.

D. Fourth Embodiment of Suspension Device A suspension device according to a fourth embodiment of the present invention is shown in FIG.
As shown in FIG. 7, the spring 31 and the damper device 40, which are constructed and assembled in the same manner as in the first to third embodiments, are provided. The feature of the fourth embodiment resides in that the air (gas) enclosed in the gas chamber R3 formed in the cylinder 40a of the damper device 40 has a spring action. Also in this case, the upper end of the piston rod 41 is fixed to the fixed plate 33 fixed to the vehicle body 22.

An inflow / outflow port 40a2 is provided in a part of the peripheral wall forming the gas chamber R3 of the cylinder 40a, and the inflow / outflow of air to / from the gas chamber R3 is controlled via the port 40a2. . In this case, if the air pressure in the gas chamber R3 is low, the elastic coefficient (spring constant) of the air is set low, and if the air pressure is high, the elastic coefficient (spring constant) of the air is set high. Therefore, the spring element of the present invention corresponds to the air (gas) enclosed in the gas chamber R3 defined by the cylinder 40a and the free piston 44.

The inflow / outflow port 40a2 is connected to the air pumps 82 and 83 via a three-position switching valve 81. The 3-position switching valve 81 is an electromagnetic solenoid 81a.
The three-position switching valve 81 is controlled to be switched by the energization control of the electromagnetic solenoid 81a by the electric control device 84. The air pumps 82 and 83 are also driven and controlled by the electric control device 84. In addition, in order to control the air pressure in the gas chamber R3, the 3-position switching valve 81
And a pressure sensor 85 is provided between the gas chamber R3 and
The pressure detection value by the sensor 85 is supplied to the electric control device 84. The three-position switching valve 81, the air pumps 82 and 83, the electric control device 84, and the pressure sensor 85 are assembled at appropriate places on the vehicle body 22.

In the vehicle suspension device according to the fourth embodiment having the above-mentioned structure, the electric control device 84 is used.
Controls the electromagnetic solenoid 81 to set the three-position switching valve 81 to the lower position shown in the figure and to operate the air pump 83.
Through the gas chamber R3. Therefore, the air pressure in the gas chamber R3 rises, and the elastic coefficient (spring constant) of the air in the gas chamber R3 increases. Then, when the elastic modulus of the air reaches a desired value is judged from the pressure value detected by the pressure sensor 85, the electric control device 84
Controls the electromagnetic solenoid 81a of the three-position switching valve 81 to switch the valve 81 to the central position shown in the figure and stops the operation of the air pump 83. as a result,
Since the inflow of air into the gas chamber R3 is stopped, the elastic modulus of air in the gas chamber R3 is maintained at the desired value.

On the other hand, if the electric control device 84 controls the electromagnetic solenoid 81a to set the 3-position switching valve 81 to the position shown in the drawing and the air pump 82 is operated, the air in the gas chamber R3 switches to the 3-position. Valve 81
It is discharged to the outside via. Therefore, in this case, the air pressure in the gas chamber R3 decreases, and the elastic coefficient (spring constant) of the air in the gas chamber R3 decreases. Also in this case, the electric control device 84 cooperates with the pressure sensor 85 to switch the three-position switching valve 81 to the illustrated central position when the elastic coefficient of the air in the gas chamber R3 reaches a desired value. At the same time, the operation of the air pump 82 is stopped. As a result, the outflow of air to the gas chamber R3 is stopped, so that the elastic modulus of the air in the gas chamber R3 is maintained at the desired value. Further, the rotational position of the step motor 49 of the damper device 40 is also controlled by the electric control device 75, and the damping coefficient of the damper device 40 is also switched.

As described above, in the suspension device according to the fourth embodiment, the lower arm (unsprung member) is used.
A spring element made of air (gas) sealed in the gas chamber R3 is provided between the body 21 and the vehicle body (spring member) 22, and the sleeve 42, the piston 43, the leaf valves 45a and 45b and the orifice in the damper device 40 are provided. It was provided in series with the damping force generating mechanism composed of the member 46. The three-position switching valve 81, the air pumps 82, 83, etc.
A spring constant variable mechanism (supply / discharge mechanism) for electrically and variably controlling the elastic coefficient (spring constant) of the air by controlling the supply / discharge of air (gas) to / from the gas chamber R3 is provided. Therefore, even with this suspension device, the spring constant of the spring element connected in series with the damper device 40 can be easily changed during traveling of the vehicle, so that even if the state of the traveling road surface, the traveling state of the vehicle, or the like changes. It is possible to constantly maintain good ride comfort, vehicle body damping, ground contact, and posture changes. Further, in the fourth embodiment, the air (gas) enclosed in the gas chamber R3, which is the spring element, is configured as a part of the damper device 40, so that the entire device is compact.

E. First Embodiment of Electric Control Device for Suspension Device Next, an electric control device 100 for a vehicle suspension according to the first to fourth embodiments configured as a to d described above.
A first embodiment of will be described. This electric control device 100 is
As shown in FIG. 8, an acceleration sensor 101 and a vehicle height sensor 102 are provided.

The acceleration sensor 101 is fixed to the vehicle body 22 or the fixing plate 33 of the first to fourth embodiments of the above suspension device, and the vehicle body 2 with respect to an absolute space is fixed.
The vertical acceleration of 2 (the sprung member) is detected, and a detection signal representing the same is output. However, the detected acceleration represents an upward acceleration by a positive value and a downward acceleration by a negative value. An integrator 103, a low pass filter 104, and a band pass filter 105 are connected to the acceleration sensor 101. The integrator 103 integrates the detection signal representing the acceleration and outputs a signal representing the vertical speed of the vehicle body 22 with respect to the absolute space (hereinafter referred to as absolute speed Zd). The low-pass filter 104 outputs the vibration component G1 of the vehicle body corresponding to the sprung resonance frequency (resonance frequency of the sprung member) by limiting and outputting the band of the detection signal indicating the acceleration to 2 Hz or less (Fig. 36). The bandpass filter 105 outputs the vibration component G2 of the vehicle body corresponding to the unsprung resonance frequency (resonance frequency of the unsprung member) by limiting the band of the detection signal indicating the acceleration to within 9 to 13 Hz and outputting the band. (See FIG. 36).

The vehicle height sensor 102 is composed of a displacement amount sensor mounted between the vehicle body 22 (sprung member) and the lower arm 21 (unsprung member), and detects the relative displacement amount of the vehicle body 22 with respect to the lower arm 21. Then, a detection signal indicating the same displacement amount is output. However, the relative displacement amount is positive when the amount of increase from the reference value (expansion side of the damper device 40) is represented, and is negative when the amount of decrease from the reference value (side of the damper device 40 is contracted). This vehicle height sensor 102
The differentiator 106 is connected. The differentiator 106 differentiates the detection signal indicating the displacement amount, and outputs a signal indicating the vertical speed of the vehicle body 22 with respect to the lower arm 21 (hereinafter, referred to as relative speed Yd).

A microcomputer 107 is connected to the integrator 103, low pass filter 104, band pass filter 105 and differentiator 106. The microcomputer 107 repeatedly executes a program corresponding to the flowcharts of FIGS. 9 to 11 every predetermined short time under the control of the built-in timer. By executing this program, the microcomputer 107 outputs a control signal for electrically controlling the spring constant of the spring element and the damping coefficient of the damper device 40 of the first to fourth embodiments to the spring constant drive circuit 108 and the damping. Coefficient driving circuit 109
To control the spring constant and the damping coefficient.

The control operation of the vehicle suspension device according to the first to fourth embodiments by the electric control device thus constructed will be described. Microcomputer 107
Starts executing the program in step 200 of FIG. 9 in response to turning on of the ignition switch, and step 2
At 02, the absolute velocity Z is calculated from the integrator 103, the low-pass filter 104, the band-pass filter 105, and the differentiator 106.
d, the vibration components G1 and G2, and the relative velocity Yd are input.

Next, by the processing of steps 204 to 222, the target spring constant K is set according to the magnitudes of the input vibration components G1 and G2. If the absolute values | G1 | and | G2 | of both vibration components G1 and G2 are greater than or equal to predetermined threshold values G10 and G20, respectively, the microcomputer 10
7 is the built-in G by the processing of steps 204 to 210.
1-K1 map (Fig. 12) and G2-K2 map (Fig. 13)
With reference to, the first and second target spring constants K1 and K2 corresponding to both vibration components G1 and G2 are determined. Note that Kmax1 and Kmax2 in FIGS. 12 and 13 have a relationship of Kmax1> Kmax2. Then, the larger value of the first and second target spring constants K1 and K2 is set as the target spring constant K by the processing of steps 212, 214 and 220. If the absolute value | G1 | of the vibration component G1 is greater than or equal to the threshold value G10 and the absolute value | G2 | of the vibration component G2 is less than the threshold value G20,
By the processing of steps 204 to 208 and 214, G1−
The first target spring constant K1 determined by referring to the K1 map is set as the target spring constant K. Absolute value of vibration component G1 |
G1 | is less than the threshold value G10 and the absolute value of the vibration component G2 |
If G2 | is the threshold value G20 or more, step 204,
Through the processing of 216 to 220, the second target spring constant K1 determined by referring to the G2-K2 map is set as the target spring constant K. Absolute values of both vibration components G1 and G2 | G1 |,
If | G2 | is less than the threshold values G10 and G20, respectively,
By the processing of steps 204, 216 and 222, the minimum spring constant Kmin is set as the target spring constant K. The target spring constant K is calculated in steps 214, 220,
In the processing of 222, when the target spring constant K determined by the processing of steps 204 to 218 increases, it is immediately changed, but when it decreases, it is not changed until a predetermined time elapses.

After setting the target spring constant K, the microcomputer 107 executes the "first spring constant setting routine" in step 224. This "first spring constant setting routine" is shown in detail in FIG. 11, and its execution is started in step 300. First, if the target spring constant K is equal to the current spring constant Know that represents the spring constant currently set in the spring element in the suspension device, this is determined in step 310 based on the determination of "YES" in step 302. The execution of the "first spring constant setting routine" is ended, and the process of changing the spring constant of the spring element in steps 302 to 308 is not performed.

If the target spring constant K is not equal to the current spring constant Know, after the determination of "YES" in step 302, the process of step 304 waits until the relative speed Yd becomes approximately "0", and then proceeds to step 306. The spring constant of the spring element is set to the target spring constant K. Step 30
In the spring constant setting process of 6, the microcomputer 107 outputs a control signal indicating the target spring constant K to the spring constant drive circuit 108, and the circuit 108 drives the spring constant variable mechanism in response to the control signal. Then, the spring constant of the spring element in the suspension device is set equal to the target spring constant K. The setting of the spring constant will be specifically described. In the suspension device of the first embodiment, the number of electromagnetic solenoids 58 corresponding to the target spring constant K is set.
Is energized, and the energization of the other electromagnetic solenoids 58 is released. As a result, as described above, only the coil spring 53 corresponding to the energized electromagnetic solenoid 58 exerts the spring action, and the spring constants of the plurality of coil springs 53 constituting the spring element of the present invention are the target spring constants. Set to K.

The case where the electric control device is applied to the second embodiment of the suspension device (see FIG. 5) will be described. 108
Then, the circuit 108 applies a control voltage corresponding to the target spring constant K to the piezoelectric actuator 66 in response to the control signal. As a result, as described above, the elastic member 61
Since the amount of hydraulic oil (liquid) corresponding to the control voltage is enclosed in the hollow portion 61b of the elastic member 61 of FIG.
Is set to the target spring constant K.

The case where this electric control device is applied to the third embodiment (see FIG. 6) of the suspension device will be described. The microcomputer 107 sends a control signal representing the target spring constant K to the spring constant drive circuit. 108
And the circuit 108 responds to the control signal by
The operations of the electromagnetic solenoid 72a of the three-position switching valve 72 and the air pumps 73, 74 are controlled with reference to the pressure detection value of the pressure sensor 76. And cylinder 4
By controlling the solubility of air (gas) in the hydraulic oil in 0a in correspondence with the target spring constant K, the elastic coefficient (spring constant) of the hydraulic oil (liquid) is set to the target spring constant K.

A case where this electric control device is applied to the fourth embodiment (see FIG. 7) of the suspension device will be described. The microcomputer 107 sends the control signal representing the target spring constant K to the spring constant drive circuit. 108
And the circuit 108 responds to the control signal by
The operations of the electromagnetic solenoid 81a of the three-position switching valve 81 and the air pumps 82, 83 are controlled with reference to the pressure detection value of the pressure sensor 85. And the gas chamber R3
By controlling the internal air pressure to a pressure corresponding to the target spring constant K, the elastic coefficient (spring constant) of the air (gas) in the gas chamber R3 is set to the target spring constant K.

After the processing of step 306, step 3
At 08, the current spring constant Know is updated to the target spring constant,
In step 310, this "first spring constant setting routine"
Ends the execution of. Next, the microcomputer 107
Controls the damping coefficient of the damping force generating mechanism incorporated in the damper device 40 according to the absolute speed Zd and the relative speed Yd by the processing of steps 226 to 234 of FIG. If the positive and negative signs of the absolute velocity Zd and the relative velocity Yd are different, step 23 is performed based on the determination of "NO" in step 226.
In step 2, the target damping coefficient C is set to the minimum damping coefficient Cmin. Then, in step 234, the microcomputer 107 outputs a control signal indicating the target damping coefficient C to the damping coefficient drive circuit 109, and the circuit 109 responds to the control signal, and in response to the control signal, the first to the first The rotation position of the step motor 49 in the damper device 40 in the fourth embodiment is controlled to a position corresponding to the target damping coefficient C.

As a result, the damping coefficient of the damping force generating mechanism in the damper device 40 is set to the minimum damping coefficient Cmin, and the same mechanism generates a small damping force. This state is a state before the wheel 11 has passed over the protrusion on the road surface as shown in S2 of FIG. 15, or a state immediately after the wheel 11 has passed over the protrusion on the road surface as shown in S4 of FIG. In these states, the vehicle body 22 is generally lifted up by an external force on the road surface or the vehicle body 22 rapidly descends. However, by keeping the damping coefficient of the damping force generating mechanism small as described above, the damper device 40 is Since the vehicle body 22 is easily displaced to the contraction side or the extension side and the push-up and the descent of the vehicle body 22 are alleviated, the ride comfort of the vehicle is kept good.

On the other hand, if the positive and negative signs of the absolute speed Zd and the relative speed Yd match, the microcomputer 107
On the basis of the determination of "YES" in step 226, the absolute speed Zd is divided by the relative speed Yd in step 228 to calculate the speed ratio Zd / Yd, and in step 230, the built-in Zd / Yd-C is calculated. Referring to the map (Fig. 14), the speed ratio Z
A target damping coefficient C corresponding to d / Yd is determined. The target damping coefficient C is set based on the skyhook theory, and is set to a value that damps the vertical vibration of the vehicle body 22 well. After the process of step 230, the rotational position of the step motor 49 in the damper device 40 is controlled to the position corresponding to the target damping coefficient C by the process of step 234 described above. It should be noted that this target damping coefficient C is immediately changed when the target damping coefficient C determined by the processing of steps 226 to 230 is increased in the processing of steps 230 and 232, but is changed when it is decreased. It is not changed until a predetermined time has passed.

As a result, the damping coefficient of the damping force generating mechanism in the damper device 40 is set to the target damping coefficient C based on the skyhook theory. This state is S3, S4 in FIG.
As shown in FIG.
The vibration of the vehicle body 22 is satisfactorily damped by the spring 31.

As can be understood from the above description of the operation,
According to the above embodiment, steps 204, 208, 216
It is detected that the vibration components G ₁ and G _{2 of} the vehicle body 22 corresponding to the sprung mass resonance frequency and the unsprung mass resonance frequency are large by the processing of step 206.
By the processing of 14, 218, 220, and 224, the spring constant of the spring element is set to a large value that increases as the vibration components G ₁ and G ₂ increase. This is the car body 2
When the vibration of No. 2 becomes large and the damping force generating mechanisms 42, 43, 45a, 45b in the damper device 40 generate a large damping force, they coincide with each other. Therefore, when the damping force generating mechanism generates a large damping force, the damping force is efficiently transmitted to the sprung member, and the damping force generated by the damping force generating mechanism is not impaired. The vibration of 22 is quickly damped. When it is not detected that the vibration components G ₁ and G ₂ are large by the processing of steps 204 and 216, the spring constant of the spring element is set to a small value by the processing of steps 222 and 224. Therefore, in this case, the small vibration of the sprung member and the road surface input are well absorbed by the spring element, and the ride comfort of the vehicle is kept good.

In particular, in the above processing, when the vibration component G ₁ corresponding to the sprung resonance frequency is large, the spring constant of the spring element is larger than when the vibration component G ₂ corresponding to the unsprung resonance frequency is large. Set to the value. As a result, the vibration of the vehicle body 22 is maximized, and the spring element and the damping force generation mechanism are effective against the vibration of the sprung member in the low frequency region where the damping force generation mechanism most effectively acts due to the responsiveness. To effectively damp the vibration.

Further, the vibration of the sprung member other than the vibration components G ₁ and G ₂ (the vibration component G ₃ located between the sprung resonance frequency and the unsprung resonance frequency and the vibration component G ₄ above the unsprung resonance frequency). ) Is large, steps 204, 216, and
By the processing of 222 and 224, the spring constant of the spring element is set to a small value. These vibration components give the occupant a lumpy feeling, and by setting the spring constant to a small value, these vibrations are absorbed by the spring element, so that the ride comfort of the vehicle becomes good.

Further, the switching control of the spring constant as described above is performed by the processing of steps 304 and 306.
This is performed only when the relative speed Yd of 2 (sprung member) to the lower arm 21 (unsprung member) is substantially "0".
Therefore, when the spring element is expanding and contracting, the spring constant of the spring element does not change, so that the occupant is not shocked by the change of the spring constant, and the ride comfort of the vehicle is improved. Become.

Moreover, according to the above embodiment, the variable control of the spring constant of these spring elements and the steps 226 to 23 are performed.
Since the control of the damping coefficient for the damping force generating mechanism consisting of 4 is simultaneously performed, the control of the damping coefficient and the control of the spring constant are appropriately controlled according to the running state of the vehicle, and the damping effect of the vibration of the sprung member and the vehicle are controlled. Both ride comfort of the car is kept good.

F. Partial Modified Example of First Embodiment of Electric Control Device In the first embodiment of the electric control device of the above e, in order to change and control the spring constant, in step 224 of FIG. 9, the “first spring constant setting routine” is executed. However, instead of this “first spring constant setting routine”, the “second spring constant setting routine” shown in FIGS.
The "spring constant setting routine" may be executed.

The execution of this "second spring constant setting routine" is started in step 400, and it is determined in step 402 whether the switching flag CHNG is "1". Since the switching flag CHNG is initially set to "0" by the initialization processing (not shown), it is determined to be "NO" in step 402 and the program is executed in step 4
Go to 04. If the target spring constant K set by the processing of steps 204 to 222 of FIG. 9 is equal to the current spring constant Know, based on the determination of “YES” in step 404, this “second spring constant setting routine” is executed in step 418. ", The spring constant of the spring element according to the first to fourth embodiments is not changed.

On the other hand, the target spring constant K is the current spring constant Know.
If not equal to, it is determined as “NO” in step 404, and the program proceeds to steps 406 to 410.
In steps 406 to 410, if the target spring constant K is larger than the current spring constant Know, the up / down flag UPDW indicating the change of the spring constant is set to "1". If the target spring constant K is smaller than the current spring constant Know, the up / down flag UPDW indicating the change of the spring constant is set to "0".
Set to. After setting the up / down flag UPDW, the switching flag CHNG is set to "4" in step 412.
Set to 1 ”and the time count value TM in step 414
Is initialized to "0", and the execution of this "second spring constant setting routine" is ended in step 426.

In this way, the switching flag CHNG
Is set to "1", "YES" is determined in step 402 of the "second spring constant setting routine" to be executed next, and the program proceeds to the "switching control routine" in step 416. This "switch control routine" is shown in detail in FIG.
It starts at 0.

As described above, the time count value TM is "0".
If set to “YE” in step 422,
Based on the judgment of "S", the program is executed in steps 424-4.
Proceed to 28. In steps 424 to 428, if the up / down flag UPDW is "1", "1" is added to the current spring constant Know. Up-down flag UP
If DW is "0", "1" is subtracted from the current spring constant Know. After updating the current spring constant Know, step 4
In the step 30, the first first spring constant setting routine shown in FIG.
The spring constant of the spring element in the suspension device according to the embodiment (or the second to third embodiments) is set to the current spring constant Know. Therefore, the target spring constant K is the current spring constant K.
If greater than now, the spring constant of the spring element in the suspension will be increased by a small amount. If the target spring constant K is smaller than the current spring constant Know, the spring constant of the spring element in the suspension device is reduced by a small amount.

In the next step 432, until the current spring constant Know becomes equal to the target spring constant K,
Continuing to determine “NO”, the time count value TM is set to a predetermined positive time value TMx in step 434, and the execution of the “switching control routine” is ended in step 440. And again, the "second spring constant setting routine"
Even when is executed, since the switching flag CHNG is set to "1" in step 438, the "switching control routine" is executed again. In this case, it is determined to be "NO" in step 422, "1" is subtracted from the time count value TM in step 438, and the execution of the routine ends. After repeatedly performing the subtraction of the time count value TM in step 438, when the count value TM becomes "0", it is determined to be "YES" again in step 422, and the program is executed from step 424 to step 424.
Proceed to 430. Therefore, the spring constant of the spring element in the suspension device gradually changes toward the target spring constant K.

In this way, when the current spring constant Know becomes equal to the target spring constant K, in step 432, "YE
S ”, and in step 436 the switching flag C
Set HNG to "0". As a result, when the “second spring constant setting routine” is executed again, it is determined to be “NO” in step 402 of FIG. 16 and the program is advanced to step 404 and thereafter. The process of changing the spring constant of the element ends. Then, if the current spring constant Know becomes not equal to the target spring constant K again, the spring constant of the spring element in the suspension device is controlled to be gradually changed toward the target spring constant K by the above-described processing. .

In this way, the microcomputer 107
Outputs the control signal for measuring the elapsed time by the processing of steps 434 and 438 and changing the spring constant of the spring element by a small amount each time the predetermined time elapses by the processing of steps 422 to 430. Therefore, even when the spring constant of the spring element is significantly changed, the spring constant is gradually changed and controlled, so that the occupant will not be shocked by the rapid change of the spring constant and the vehicle ride Feels good.

G. Second Embodiment of Electric Control Device for Suspension Device Next, the electric control device 100 for a vehicle suspension according to the first to fourth embodiments configured as a to d described above.
A second embodiment will be described. This electric control device is shown in FIG.
As shown in FIG. 6, in addition to the circuits of the first embodiment of the electric control device 100, a low-pass filter 111 connected to the output of the integrator 103, a low-pass filter 112 connected to the differentiator 106, and a band-pass filter, respectively. Filter 1
13, 114 and a high pass filter 115.

The low pass filter 111 comprises an integrator 103.
The band of the signal representing the vertical speed of the sprung member from is limited to 2 Hz or less, and the limited signal is output as a signal representing the absolute speed Zd of the sprung member. The low-pass filter 112 limits the band of the signal representing the relative speed of the sprung member to the unsprung member from the differentiator 106 to 2 Hz or less, and outputs the limited signal as a signal representing the relative speed Yd of the sprung member. To do. Bandpass filter 1
13 is a sprung member in the frequency band between the sprung resonance frequency and the unsprung resonance frequency for limiting the band of the signal representing the relative speed from the differentiator 106 within 3 to 7 Hz, respectively. Is output as a signal representing the relative speed V3 of the. The bandpass filter 114 includes the differentiator 10
The signal bands representing the relative speed from 6 are 9 to
It is limited to 13 Hz, and the limited signal is output as a signal representing the relative speed V2 of the sprung member in the unsprung resonance frequency band. The high pass filter 115 is a differentiator 1
The band of the signal indicating the relative velocity from 06 is limited to 13 Hz or more, and the limited signal is output as a signal indicating the relative velocity V4 of the sprung member in the frequency region higher than the unsprung resonance frequency. In addition, the microcomputer 107
In this case, the program corresponding to the flowcharts of FIGS. 19 and 20 is executed at predetermined short time intervals under the control of the built-in timer.

The control operation of the vehicle suspension device according to the first to fourth embodiments (a) to (d) by the electric control device 100 thus configured will be described. In response to the ignition switch being turned on, the microcomputer 107 starts executing the program in step 500 of FIG. 19, and in step 502, the low-pass filters 111, 1
04, band pass filter 105, low pass filter 1
12, the absolute velocity Zd, the vibration components G1 and G2, and the relative velocities Yd, V3, V2, and V4 are input from the bandpass filters 113 and 114 and the highpass filter 115, respectively.

Next, the same step 2 as in the first embodiment.
By the processing of 04 to 224, the input vibration component G1,
The target spring constant K is determined according to the magnitude of G2, and the spring constant of the spring element in the suspension device is controlled to be equal to the determined target spring constant K.

After the processing of steps 204 to 224, the microcomputer 107 executes step 226 of FIG.
To 234 and 504 to 512, the damper device 4
The damping force generating mechanisms 42, 43, 45a, 45 are controlled by controlling the damping coefficient varying mechanisms 48, 49 incorporated in the 0.
The damping coefficients b and 46 are set to the target damping coefficient C. In this case, only when the vibration component G1 corresponding to the sprung resonance frequency is equal to or greater than the predetermined threshold value G10 and the absolute velocity Zd and the relative velocity Yd have the same sign, the steps 504, 2 are performed.
Based on the determination of “YES” in 26, the damping coefficient of the damping force generation mechanism is set to the target damping coefficient C based on the skyhook theory by the processing of steps 228, 230, and 234 similar to the first embodiment. To be done. However, the absolute velocity Zd and the relative velocity Yd in this case consist only of frequency components belonging to the resonance frequency region of the vehicle body 22 (spring member).

Vibration component G1 corresponding to the sprung resonance frequency
Is less than a predetermined threshold value G10 or the absolute velocity Zd and the relative velocity Yd have different signs, at step 506 the absolute values | V3 |, | of the relative velocities V3, V4 of the sprung member
The vibration component KG (= a · | V3 | + b · | V4 |) is calculated by multiplying V4 | by appropriate positive coefficients a and b, respectively. This vibration component KG corresponds to the vibration component of the sprung member outside the sprung resonance frequency region and the unsprung resonance frequency region.
If the vibration component KG is equal to or greater than the predetermined threshold value KG0, the target damping coefficient C is set to the minimum value C in step 232 based on the determination of "YES" in step 508.
min (see FIG. 14), and the damping coefficient of the damping force generating mechanism is set to the minimum value Cmin by the processing of step 234. Thereby, for vibration of the sprung member outside the sprung resonance frequency region and the unsprung resonance frequency region,
The damping coefficient of the damping force generating mechanism is set to a small value, and the ride comfort of the vehicle becomes good.

Further, the vibration component KG has a predetermined threshold value KG.
Even if it is less than 0, as long as the relative speed V2 is not greater than or equal to the predetermined threshold value V20, "N" in steps 508 and 510 is set.
Based on the determination of "O", the damping coefficient of the damping force generation mechanism is set to a small value by the processing of steps 232 and 234, and the ride comfort of the vehicle is kept good. On the other hand, if the relative speed V2 is greater than or equal to the threshold value V20, it is determined to be "YES" in step 510, and the damping coefficient of the damping force generating mechanism is set to an intermediate value Cmid larger than the minimum value Cmin by the processing of step 512. (See FIG. 14). this is,
When the vibration of the vehicle body 22 is generated in the frequency region corresponding to the unsprung resonance frequency, the damping coefficient of the damping force generating mechanism is increased to some extent to quickly damp the vibration related to the unsprung resonance of the vehicle body 22. This is because.

As described above, according to this embodiment, when the vibration component of the sprung member that belongs to the high frequency region is large, the damping coefficient of the damping force generating mechanism is set small. Therefore, due to the poor responsiveness of the damping force varying mechanisms 48, 49 and the damping force generating mechanisms 42, 43, 45a, 45b, 46, both mechanisms cannot satisfactorily damp the vibration of the sprung member. In the frequency domain, the ride comfort of the vehicle is prioritized without wasteful vibration damping control.

When the vibration component of the sprung member corresponding to the sprung resonance frequency is large, steps 504 and 2 are performed.
By the processing of 28, 230, and 234, the damping coefficient of the damping force generating mechanism is set to the first value that increases as the vibration of the sprung member increases. When the vibration component of the sprung member corresponding to the unsprung resonance frequency is large, the damping coefficient is set to the small second value Cmid by the processing of steps 510 and 512. In other cases, especially when the vibration components of the sprung member and the unsprung member are large, the damping coefficient is set to the third value smaller than the second value Cmid by the processing of steps 504, 506, 508, and 510. Set to Cmin. With this, the vibration of the sprung member is finely controlled for each frequency, and it is possible to better achieve both the damping of the vibration of the sprung member and the improvement of the riding comfort of the vehicle.

In this second embodiment, the relative speed V2
.About.V4 is used to control the damping coefficient of the damping force generating mechanism. However, this relative speed V2 to V4 is
Since it is used as a detection amount for detecting the vibration of 2 (spring member), the vehicle body 2 is replaced by these relative speeds V2 to V4.
Similar results can be obtained by using each frequency component of the vertical acceleration of 2. In this case, the output of the acceleration sensor 101 of FIG. 18 is connected to the bandpass filter 116 having a passband of 3 to 7 Hz and the highpass filter 117 having a passband of 15 Hz or more. Then, the microcomputer 107 executes step 5 in FIG.
At 02, the vibration components G3 and G4 (see FIG. 36) which are the outputs of the filters 116 and 117 are input, and step 5
The vibration component G at 06 and 510 instead of the relative speeds V2 to V4.
2 to G4 may be used.

H. Third Embodiment of Electric Control Device for Suspension Device Next, an electric control device 100 for a vehicle suspension according to the first to fourth embodiments configured as a to d described above.
A third embodiment will be described. This electric control device 100 is
As shown in FIG. 21, in addition to the circuits of the first embodiment of the electric control device of the above f, the same bandpass filter 116 and high pass filter 117 as those of the modification of the second embodiment of the electric control device of the above g are used. And a steering angle sensor 12
1, a differentiator 122, a vehicle speed sensor 123, an engine speed sensor 124, and a brake switch 125.

The steering angle sensor 121 detects the rotation angle θ of the steering wheel from the reference position, and the differentiator 122 detects the rotation angle θ.
A signal representing the steering speed θv is output by differentiating. The vehicle speed sensor 123 detects and outputs the vehicle speed V.
The engine speed sensor 124 detects and outputs the engine speed Ne. The brake switch 125 is turned on when the brake pedal is depressed, and the high level is "1".
And outputs a brake signal BR indicating Further, in this case, the microcomputer 107 executes the program corresponding to the flow charts of FIGS. 22 to 26 at every predetermined short time under the control of the built-in timer.

The control operation of the vehicle suspension apparatus according to the first to fourth embodiments (a) to (d) by the thus configured electric control device 100 will be described. In response to the ignition switch being turned on, the microcomputer 107 starts executing the program in step 600 of FIG. 22, and in step 602, the integrator 103, the low-pass filter 104, the band-pass filters 116 and 105, the high-pass filter 117, and the derivative. The absolute speed Zd, the vibration components G1 to G4, the relative speed Yd, the steering speed θv, the vehicle speed V, the engine speed Ne from the devices 106 and 122, the vehicle speed sensor 123, the engine speed sensor 124, and the brake switch 125.
And the brake signal BR are input respectively.

After the processing of step 602, step 6
In 04, the absolute values of the input vibration components G3 and G4 |
By multiplying G3 | and | G4 | by appropriate positive coefficients c and d, respectively, and adding the respective multiplication results, the sum of vibration components Gt (= c. | G3 | + d. | G4 |) is calculated. next,
By the processing of steps 606 to 618, the spring constant Kθ related to the steering speed θv is determined. If the absolute value | θv | of the steering speed θv is less than the predetermined threshold value θv0, the spring constant Kθ is set to a predetermined minimum spring constant Kmin (FIG. 27) by the processing of steps 606 and 608.

If the absolute value | θv | of the steering speed θv is not less than the predetermined threshold θv0, steps 606 and 610
Of the built-in θ in the microcomputer 107
For the time being, referring to the v-Kθ map (FIG. 27), the spring constant Kθ is set to a value that increases as the absolute value | θv | increases. In this case, if the calculated vibration component sum Gt is less than the predetermined threshold value Gt10, the spring constant Kθ is maintained at the set value based on the determination of “NO” in step 612.

On the other hand, if the vibration component sum Gt is greater than or equal to the threshold value Gt10, the spring constant KG1 is determined by the processing of steps 612 and 614 with reference to the Gt-KG1 map (FIG. 28) built in the microcomputer 107. Vibration component sum G
Set a value that decreases as t increases.
Thereafter, by the processing of steps 616 and 618, if the spring constant KG1 is smaller than the spring constant Kθ, the spring constant Kθ
To the spring constant KG1.

Next, the spring constant KV related to the vehicle speed V is determined by the processing of steps 620 to 632 of FIG. If the vehicle speed V is less than the predetermined threshold value V0, the spring constant KV is set to a predetermined minimum spring constant Kmin (FIG. 29) by the processing of steps 620 and 622. Also,
If the vehicle speed V is equal to or higher than the predetermined threshold value V0, step 6
By the processing of 20,624, the microcomputer 10
Referring to the V-KV map (FIG. 29) built in 7, the spring constant KV is set to a value that increases as the vehicle speed V increases for the time being. In this case, if the calculated vibration component sum Gt is less than the predetermined threshold value Gt20, the spring constant KV is maintained at the set value based on the determination of "NO" in step 626.

On the other hand, if the vibration component sum Gt is greater than or equal to the threshold value Gt20, the spring constant KG2 is determined by the processing of steps 626 and 628 with reference to the Gt-KG2 map (FIG. 30) built in the microcomputer 107. Vibration component sum G
Set a value that decreases as t increases.
After that, if the spring constant KG2 is smaller than the spring constant KV by the processing of steps 630 and 632, the spring constant KV
To the spring constant KG2.

Next, the spring constant KN related to the engine speed Ne (accelerating operation of the vehicle) is determined by the processing of steps 634 to 646 of FIG. Engine speed Ne
Is less than the predetermined threshold Ne0, step 634,
By the processing of 636, the spring constant KN is determined to a predetermined minimum spring constant Kmin (FIG. 31). If the engine speed Ne is equal to or higher than a predetermined threshold value Ne0,
By the processing of steps 634 and 638, referring to the Ne-KN map (FIG. 31) built in the microcomputer 107, for the time being, the spring constant KN is set to the engine speed N.
The value is set to increase as e increases.
In this case, if the calculated vibration component sum Gt is less than the predetermined threshold value Gt30, "N" in step 640.
Based on the determination of "O", the spring constant KN is maintained at the value set above.

On the other hand, if the vibration component sum Gt is greater than or equal to the threshold value Gt30, the spring constant KG3 is determined by the processing of steps 640 and 642 with reference to the Gt-KG3 map (FIG. 32) built in the microcomputer 107. Vibration component sum G
Set a value that decreases as t increases.
After that, if the spring constant KG3 is smaller than the spring constant KV by the processing of steps 644 and 646, the spring constant KV.
To the spring constant KG3.

Next, the spring constant KB related to the depression operation of the brake pedal (deceleration operation of the vehicle) is determined by the processing of steps 648 to 660 in FIG. If the brake switch 125 is off without pressing the brake pedal, the processing of steps 648 and 650 causes
The spring constant KB is set to a predetermined minimum spring constant Kmin. When the brake pedal is depressed and the brake switch 125 is turned on, the spring constant KB is set to a predetermined value KBon (> Kmin) determined in advance by the processing of steps 648 and 652. In this case, if the calculated vibration component sum Gt is less than the predetermined threshold value Gt40, based on the determination of "NO" in step 654,
The spring constant KB is maintained at the value set above.

On the other hand, if the vibration component sum Gt is greater than or equal to the threshold value Gt40, the spring constant KG4 is determined by the processing of steps 654 and 656 with reference to the Gt-KG4 map (FIG. 33) built in the microcomputer 107. Vibration component sum G
Set a value that decreases as t increases.
After that, if the spring constant KG4 is smaller than the spring constant KB by the processing of steps 658 and 660, the spring constant KB is
To the spring constant KG4.

Next, at step 662, the maximum value of the determined spring constants Kθ, KV, KN and KB is set as the target spring constant K. After setting the target spring constant K, in step 224, the "first spring constant setting routine" (or the "second spring constant setting routine" in the above f) similar to the first embodiment of the electric control device 100 described in e above. By executing the above, the spring constant of the spring element in the suspension device is controlled to be equal to the determined target spring constant K.

Next, the microcomputer 107 determines the damping coefficient of the damping force generating mechanism incorporated in the damper device 40 based on the skyhook theory by the processing of steps 226 to 234 of FIG. 26 similar to the above embodiment. The target damping coefficient C is controlled.

As can be understood from the above description of the operation, according to this embodiment, the steering angle sensor 121, the engine speed sensor 124 and the brake switch 125 are used to change the posture of the sprung member (vehicle body 22) (roll, dive, The driving operation amount of the vehicle that causes the squat is detected, and it is determined by the processing of steps 606, 634, and 648 whether the driving operation amount is large. If the driving operation amount is large, steps 610, 638, 652 are performed. By the processing of 1, the spring constants Kθ, KN, and KB that increase with an increase in the operation amount are determined. When the driving operation amount is small, the spring constants Kθ, KN and KB are set to small values by the processing of steps 608, 636 and 650. Further, the vehicle speed V is detected by the vehicle speed sensor 123, and the vehicle speed V is detected by the processing of step 620.
Is determined to be large, and if the vehicle speed V is large, the spring constant KV that increases as the vehicle speed V increases is determined by the process of step 624. When the vehicle speed V is low, the spring constant KV is set to a small value by the processing of step 622. And step 66
2,224, the spring constants Kθ, K
The spring constant of the spring element is controlled to the largest value among N, KB and KV.

Therefore, the state in which the posture of the sprung member changes and the damping force generating mechanisms 42, 43, 45a, 45b, 46 generate the damping force is steps 606, 634, 648.
Is detected by the processing of step (1), and at the same time, the spring constant of the spring element is set to a large value. As a result, the spring element efficiently transmits the damping force to the sprung member even when the posture of the sprung member changes due to the driving operation and the damping force generating mechanism generates the damping force. The vibration of is well damped.
Further, even when the vehicle speed V is high, the spring constant of the spring element is set to a large value. Therefore, even if the vehicle turns by the turning operation of the steering wheel during high speed traveling, the damping force generated by the damping force generation mechanism is the spring force. The vibration of the sprung member due to vehicle turning can be effectively attenuated by being efficiently transmitted to the upper member.

Also, in this embodiment, step 6
By the processing of 04, the vibration component Gt of the sprung member in the frequency region not corresponding to the sprung resonance frequency and the unsprung resonance frequency is calculated, and steps 612 to 618, 626 are calculated.
˜632, 640 to 646, 654 to 660, when the vibration component Gt is large, the spring constant K is
The upper limits of θ, KN, KB and KV are limited. Therefore, when this vibration component Gt is large, the spring constant of the spring element is suppressed to a small value. Here, the vibration component Gt is a component that gives a rugged feeling to the occupant, but since the generation of the damping force in the damping force generation mechanism is suppressed by suppressing the spring constant to be small, the riding comfort of the vehicle is improved. To be kept.

In this embodiment, the acceleration of the vehicle is detected by the engine speed sensor 124. Instead of this, an acceleration sensor for detecting the longitudinal acceleration of the vehicle is used, or the accelerator pedal is depressed. An accelerator opening sensor that detects the amount may be used.
Although the deceleration of the vehicle is detected by the brake switch 125, the acceleration sensor may be used instead of the brake switch 125.

[Brief description of drawings]

FIG. 1 is a first conceptual diagram for explaining a solution principle of the present invention.

FIG. 2 is a second conceptual diagram for explaining a solution principle of the present invention.

FIG. 3 is a schematic sectional view showing a first embodiment of a vehicle suspension device according to the present invention.

FIG. 4 is an enlarged view showing a part of the damper device of FIG. 3 accurately.

FIG. 5 is a schematic cross-sectional view showing a second embodiment of the vehicle suspension device according to the present invention.

FIG. 6 is a schematic sectional view showing a third embodiment of the vehicle suspension device according to the present invention.

FIG. 7 is a schematic cross-sectional view showing a fourth embodiment of the vehicle suspension device according to the present invention.

FIG. 8 is a block diagram showing a first embodiment of an electric control device for a vehicle suspension device according to the present invention.

9 is a flowchart showing a first half of a program executed by the microcomputer shown in FIG.

FIG. 10 is a flowchart showing the latter half of the program.

FIG. 11 is a flowchart showing details of a first spring constant setting routine of FIG. 9.

FIG. 12 shows a G provided in the microcomputer shown in FIG.
It is a graph which shows the change characteristic of the 1st target spring constant K1 to vibration component G1 in the 1-K1 map.

FIG. 13: G2- provided in the same microcomputer
It is a graph which shows the change characteristic of the 1st target spring constant K2 with respect to the vibration component G2 in a K2 map.

FIG. 14 shows Zd / provided in the same microcomputer.
It is a graph which shows the change characteristic of damping coefficient C to speed ratio Zd / Yd in a Yd-C map.

FIG. 15 A vehicle body when wheels pass through a protrusion on the road surface,
It is a schematic diagram which shows the changed state of a damper apparatus and a spring.

16 is a flowchart showing details of a second spring constant setting routine that replaces the first spring constant setting routine of FIG.

FIG. 17 is a flowchart showing details of the switching control routine of FIG.

FIG. 18 is a block diagram showing a second embodiment of an electric control device for a vehicle suspension device according to the present invention.

FIG. 19 is a flowchart showing the first half of a program executed by the microcomputer shown in FIG.

FIG. 20 is a flowchart showing the latter half of the program.

FIG. 21 is a block diagram showing a third embodiment of an electric control device for a vehicle suspension device according to the present invention.

22 is a flowchart showing the first part of a program executed by the microcomputer of FIG. 21. FIG.

FIG. 23 is a flowchart showing the next part of the same program.

FIG. 24 is a flowchart showing the next part of the program.

FIG. 25 is a flowchart showing the next part of the same program.

FIG. 26 is a flowchart showing the final part of the program.

27 is a graph showing change characteristics of a target spring constant Kθ with respect to a steering speed θv in a θv-Kθ map provided in the microcomputer of FIG.

FIG. 28 is a graph showing change characteristics of the spring constant KG1 with respect to the vibration component Gt in the Gt-KG1 map provided in the same computer.

FIG. 29 is a graph showing a change characteristic of a target spring constant KV with respect to a vehicle speed V in a V-KV map provided in the same computer.

FIG. 30 is a graph showing change characteristics of a spring constant KG2 with respect to a vibration component Gt in a Gt-KG2 map provided in the same computer.

FIG. 31 is a graph showing a change characteristic of a target spring constant KN with respect to an engine rotation speed Ne in a Ne-KN map provided in the same computer.

FIG. 32 is a graph showing change characteristics of a spring constant KG3 with respect to a vibration component Gt in a Gt-KG3 map provided in the same computer.

FIG. 33 is a graph showing change characteristics of a spring constant KG4 with respect to a vibration component Gt in a Gt-KG4 map provided in the same computer.

FIG. 34 is a perspective view of a conventional vehicle suspension device.

FIG. 35 is a conceptual diagram equivalent to the suspension device.

FIG. 36 is a frequency distribution diagram of various vibrations that cause vehicle body vibrations.

[Explanation of symbols]

11 ... Wheels, 12 ... Lower arm (unsprung member), 13 ...
Vehicle body (spring member) 14 ... Spring, 15a ... Damping force generating mechanism, 17 ... Electric control device, 18 ... Spring element, 21
... lower arm, 22 ... car body, 31 ... spring, 40 ...
Damper device, 40a ... Cylinder, R1 ... Upper oil chamber, R2 ...
Lower oil chamber, R3 ... Gas chamber, 41 ... Piston rod, 42 ...
Sleeves 42a to 42d ... Oil passage (orifice), 43
... Pistons, 43a, 43b ... Oil passages (orifices), 4
4 ... Free piston, 45a, 45b ... Leaf valve,
46 ... Orifice member, 48 ... Nut, 49 ... Step motor, 51 ... Movable plate, 53 ... Spring, 54
... control rod, 57 ... clutch bar, 58 ... electromagnetic solenoid, 61 ... elastic member, 64 ... cylinder, 65
a, 65b ... Piston, 66 ... Piezoelectric actuator, 6
7 ... Electric control device, 71 ... Filter, 72, 81 ... 3 position switching valve, 73, 74, 82, 83 ... Air pump, 75, 84 ... Electric control device, 100 ... Electric control device, 101 ... Acceleration sensor, 102 ... Vehicle height sensor, 10
3 ... Integrator, 104, 111, 112 ... Low pass filter, 105, 113, 114, 116 ... Band pass filter, 106, 122 ... Differentiator, 107 ... Microcomputer, 108 ... Spring constant drive circuit, 109 ... Damping coefficient Drive circuit, 115, 117 ... High-pass filter,
121 ... Rudder angle sensor, 123 ... Vehicle speed sensor, 124 ... Engine frequency sensor, 125 ... Brake switch.

Front Page Continuation (72) Inventor Saku Saku 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (72) Inventor Mitsunobu Hattori 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (72) Invention Person Yasuhiko Sanshio 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Corporation (72) Inventor Hiroyoshi Kojima 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation

Claims (21)

[Claims] 1. A spring for elastically supporting an unsprung member with respect to an unsprung member between an unsprung member and an unsprung member, and a vibration of a sprung member with respect to the unsprung member by generating a damping force. In a vehicle suspension device provided in parallel with a damping force generation mechanism that damps, a spring element arranged in series with the damping force generation mechanism between an unsprung member and an unsprung member, and electrically controlled. And a spring constant changing mechanism capable of changing the spring constant of the spring element. 2. The vehicle suspension device according to claim 1, wherein the spring element is provided between the damping force generating mechanism and a sprung member. 3. The vehicle suspension device according to claim 1, wherein the spring element is provided between the damping force generating mechanism and an unsprung member. 4. A spring which is provided between the unsprung member and the unsprung member and elastically supports the unsprung member with respect to the unsprung member; And a piston rod having a lower end portion connected to the piston and an upper portion protruding from the upper end surface of the cylinder so as to be movable up and down. In a vehicle suspension device including a damper device that generates a damping force along with the movement of the piston by communicating through an orifice, the suspension device for a vehicle is interposed between an upper end portion of the piston rod and a sprung member. A plurality of springs and a spring selection mechanism that is electrically controlled to selectively exert the spring action of the plurality of springs. Dual suspension system. 5. A spring which is provided between the unsprung member and the unsprung member and elastically supports the unsprung member with respect to the unsprung member; And a piston rod having a lower end portion connected to the piston and an upper portion protruding from the upper end surface of the cylinder so as to be movable up and down. A suspension device for a vehicle, comprising: a damper device that generates a damping force in accordance with the movement of the piston by communicating with each other through an orifice, wherein the interior of the suspension device is interposed between an upper end portion of the piston rod and a sprung member. An elastic member in which a liquid is sealed, and a supply / discharge device that is electrically controlled to control the supply / discharge of the liquid in the elastic member to change the amount of the liquid sealed in the elastic member. Vehicle suspension apparatus characterized by comprising a structure. 6. A spring, which is provided between the unsprung member and the unsprung member, and elastically supports the unsprung member with respect to the unsprung member; And a piston rod having a lower end portion connected to the piston and an upper portion protruding from the upper end surface of the cylinder so as to be movable up and down. In a vehicle suspension device including a damper device that generates a damping force along with the movement of the piston by communicating through an orifice, a gas is dissolved in the liquid in the cylinder, and A vehicle, characterized by being provided with a supply / discharge mechanism for controlling the supply / discharge of gas to / from the cylinder to change the amount of gas dissolved in the liquid. Scan pension system. 7. A spring which is provided between the unsprung member and the unsprung member and elastically supports the unsprung member with respect to the unsprung member; A cylinder which is enclosed by a piston and is divided into upper and lower chambers by a piston, a piston rod whose lower end is connected to the piston and whose upper part is vertically movably projected from the upper end surface of the cylinder, and below the piston. A damper device that is built into a cylinder and that comprises a free piston that forms a gas chamber below the lower chamber, and that communicates the upper and lower chambers via an orifice to generate a damping force with the movement of the piston. In a suspension device for a vehicle equipped with, a supply / exhaust mechanism that is electrically controlled to control supply / exhaust of gas to / from the gas chamber and change gas pressure in the gas chamber. Vehicle suspension system, characterized in that provided. 8. A spring for elastically supporting the sprung member with respect to the unsprung member between the unsprung member and the unsprung member, and a vibration of the sprung member with respect to the unsprung member by generating a damping force. And a spring element arranged in series between the unsprung member and the unsprung member in series with the damping force generating mechanism that damps the spring element, and the spring element electrically controlled. An electric control device for a vehicle suspension device applied to a vehicle suspension device having a spring constant variable mechanism capable of changing the spring constant of the device, wherein the damping force generation mechanism detects a state in which a damping force is generated. And a spring constant control means for increasing the spring constant of the spring element by controlling the spring constant changing mechanism when the state is detected by the detecting means. Electric control apparatus for use suspension device. 9. A spring for elastically supporting the sprung member with respect to the unsprung member between the unsprung member and the unsprung member, and a vibration of the sprung member with respect to the unsprung member by generating a damping force. And a spring element arranged in series between the unsprung member and the unsprung member in series with the damping force generating mechanism that damps the spring element, and the spring element electrically controlled. An electric control device for a vehicle suspension device applied to a vehicle suspension device having a spring constant variable mechanism capable of changing the spring constant of, a vibration detecting unit for detecting vibration of a sprung member, Spring constant control means for increasing the spring constant of the spring element by controlling the spring constant changing mechanism when the detected vibration is large. The control device. 10. The vibration detecting means according to claim 9,
An electric control device for a vehicle suspension device, which detects vibration of a sprung member in a specific frequency range. 11. A spring for elastically supporting the sprung member with respect to the unsprung member between the unsprung member and the unsprung member, and a vibration of the sprung member with respect to the unsprung member by generating a damping force. And a spring element arranged in series between the unsprung member and the unsprung member in series with the damping force generating mechanism that damps the spring element, and the spring element electrically controlled. Is an electric control device for a vehicle suspension device applied to a vehicle suspension device including a spring constant variable mechanism capable of changing the spring constant of the vehicle, and a vehicle driving operation causing a posture change of a sprung member. And a spring constant control unit for controlling the spring constant variable mechanism and increasing the spring constant of the spring element in response to the vehicle driving operation detected by the detection unit. Electric control apparatus for a vehicle suspension system according to claim. 12. A spring for elastically supporting the sprung member with respect to the unsprung member between the unsprung member and the unsprung member, and vibration of the sprung member with respect to the unsprung member by generating a damping force. And a spring element arranged in series between the unsprung member and the unsprung member in series with the damping force generating mechanism that damps the spring element, and the spring element electrically controlled. An electric control device for a vehicle suspension device applied to a vehicle suspension device having a spring constant variable mechanism capable of changing the spring constant of the vehicle, the vehicle speed detecting means for detecting a vehicle speed, and the detected vehicle speed. And a spring constant control means for controlling the spring constant varying mechanism to increase the spring constant of the spring element when the electric constant is large. 13. A spring for elastically supporting the sprung member with respect to the unsprung member between the unsprung member and the unsprung member, and a vibration of the sprung member with respect to the unsprung member by generating a damping force. And a spring element arranged in series between the unsprung member and the unsprung member in series with the damping force generating mechanism that damps the spring element, and the spring element electrically controlled. Applied to a vehicle suspension device having a spring constant changing mechanism capable of changing the spring constant of the target, and outputting a control signal to the spring constant changing mechanism to cause the spring constant of the spring element to be represented by the control signal. An electric control device for a vehicle suspension device set to a spring constant, wherein the electric control device detects a vibration component of a sprung member distributed between resonance frequencies of a sprung member and an unsprung member. And a spring constant regulating unit that regulates a target spring constant represented by the control signal to a small value when the detected vibration component is large. Electric control device. 14. A spring for elastically supporting the sprung member with respect to the unsprung member between the unsprung member and the unsprung member, and a vibration of the sprung member with respect to the unsprung member by generating a damping force. And a spring element arranged in series between the unsprung member and the unsprung member in series with the damping force generating mechanism that damps the spring element, and the spring element electrically controlled. Is applied to a vehicle suspension device equipped with a spring constant variable mechanism capable of changing the spring constant, and an electric control for a vehicle suspension device that outputs a control signal for spring constant switching control to the spring constant variable mechanism. In the electric control device, the relative speed detecting means for detecting the relative speed of the sprung member with respect to the unsprung member, and the relative speed detected by the relative speed detecting means are substantially equal to each other. Electric control apparatus for a vehicle suspension system, characterized in that a and permitting means for permitting the output of the control signal when it is ". 15. A spring for elastically supporting the sprung member with respect to the unsprung member between the unsprung member and the unsprung member, and vibration of the sprung member with respect to the unsprung member by generating a damping force. And a spring element arranged in series between the unsprung member and the unsprung member in series with the damping force generating mechanism that damps the spring element, and the spring element electrically controlled. Is applied to a vehicle suspension device equipped with a spring constant variable mechanism capable of changing the spring constant, and a vehicle suspension device for switching the spring constant of the spring element by electrically controlling the spring constant variable mechanism. An electric control device, wherein a switching control hand that forms a control signal for gradually changing the spring constant when switching the spring constant in the electric control device and outputs the control signal to the spring constant varying mechanism. An electric control device for a vehicle suspension device, characterized in that a step is provided. 16. A spring, which is disposed between the unsprung member and the unsprung member and elastically supports the unsprung member with respect to the unsprung member, and between the unsprung member and the unsprung member. A damping force generation mechanism that is arranged in parallel with the spring to generate a damping force to damp the vibration of the sprung member with respect to the unsprung member, and a damping force generation mechanism between the unsprung member and the sprung member in series A spring element provided in the spring, a damping coefficient variable mechanism that can be electrically controlled to change the damping coefficient of the damping force generating mechanism, and a spring constant variable mechanism that can be electrically controlled to change the spring constant of the spring element. And an electric control device for electrically controlling the damping coefficient varying mechanism and the spring constant varying mechanism. 17. A spring disposed between the unsprung member and the unsprung member to elastically support the unsprung member with respect to the unsprung member, and between the unsprung member and the unsprung member. A damping force generation mechanism that is arranged in parallel with the spring to generate a damping force to damp the vibration of the sprung member with respect to the unsprung member; and a damping force generation mechanism between the unsprung member and the sprung member in series with the damping force generation mechanism. , A damping element variable mechanism that can be electrically controlled to change the damping coefficient of the damping force generating mechanism, and a spring constant variable that can be electrically controlled to change the spring constant of the spring element. An electric control device for a vehicle suspension device applied to a vehicle suspension device including a mechanism, comprising: first vibration detecting means for detecting vibration of a sprung member; Shaking A second vibration detecting means for detecting the vibration damping force, and a first vibration damping means for controlling the damping coefficient variable mechanism when the vibration of the sprung member detected by the first vibration detecting means is large to set a large damping coefficient for the damping force generating mechanism. Control means, and second control means for controlling the spring constant varying mechanism to set a large spring constant of the spring element when the vibration of the sprung member in the specific frequency region detected by the second vibration detecting means is large. An electric control device for a vehicle suspension device, comprising: 18. The specific frequency range of the vibration of the sprung member detected by the second vibration detecting means according to claim 17 is at least one of resonance frequencies of the sprung member and the unsprung member. An electrical control device for a vehicle suspension device that is compatible with a resonance frequency. 19. A spring disposed between the unsprung member and the unsprung member to elastically support the unsprung member with respect to the unsprung member, and between the unsprung member and the unsprung member. A damping force generation mechanism that is arranged in parallel with the spring to generate a damping force to damp the vibration of the sprung member with respect to the unsprung member; and a damping force generation mechanism between the unsprung member and the sprung member in series with the damping force generation mechanism. , A damping element variable mechanism that can be electrically controlled to change the damping coefficient of the damping force generating mechanism, and a spring constant variable that can be electrically controlled to change the spring constant of the spring element. An electric control device for a vehicle suspension device applied to a vehicle suspension device including a mechanism, comprising: a sensor for detecting vibration of a sprung member; and a vibration sensor of the sprung member detected by the sensor. When the vibration component belonging to the low frequency region is large, the damping coefficient variable mechanism is controlled to increase the damping coefficient of the damping force generation mechanism as the vibration of the sprung member detected by the sensor increases, and First control means for controlling the damping coefficient variable mechanism to set a small damping coefficient of the damping force generation mechanism when the vibration component is small; and vibration of the sprung member detected by the sensor belongs to a specific frequency range. When the vibration of the sprung member is large, the spring constant variable mechanism is controlled to set the spring constant of the spring element large, and in other cases, the spring constant variable mechanism is controlled to reduce the spring constant of the spring element. An electric control device for a vehicle suspension device, comprising: a second control means for setting. 20. The specific frequency range of vibration of the sprung member in the second control means according to claim 19, corresponds to at least one of resonance frequencies of the sprung member and the unsprung member. An electric control device for a vehicle suspension device. 21. A spring arranged between the unsprung member and the unsprung member to elastically support the unsprung member with respect to the unsprung member; and between the unsprung member and the unsprung member. A damping force generation mechanism that is arranged in parallel with the spring to generate a damping force to damp the vibration of the sprung member with respect to the unsprung member; and a damping force generation mechanism between the unsprung member and the sprung member in series with the damping force generation mechanism. , A damping element variable mechanism that can be electrically controlled to change the damping coefficient of the damping force generating mechanism, and a spring constant variable that can be electrically controlled to change the spring constant of the spring element. An electric control device for a vehicle suspension device applied to a vehicle suspension device including a mechanism, comprising: a sensor unit that detects vibration of a sprung member; and a sprung member that is detected by the sensor unit. When the vibration component corresponding to the resonance frequency of the sprung member is large in the motion, the damping coefficient varying mechanism is controlled to a first value that increases as the vibration of the sprung member detected by the sensor means increases. The damping coefficient of the damping force generating mechanism is set, and when the detected vibration of the sprung member has a large vibration component corresponding to the resonance frequency of the unsprung member, the damping coefficient variable mechanism is controlled to reduce the damping coefficient. When the vibration component corresponding to each resonance frequency of the unsprung member and the sprung member of the detected vibration of the sprung member is not large, the damping coefficient variable mechanism is controlled to set the damping coefficient to the second value. Is a third value smaller than the second value
And a spring constant when the vibration of the sprung member corresponding to each resonance frequency of the sprung member and the unsprung member is large among the vibrations of the sprung member detected by the sensor means. An electric control device for a vehicle suspension device, comprising: a second control means for controlling a variable mechanism to set a large spring constant of the spring element.